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In this report, the geometric and electronic properties and static and dynamic hyperpolarizabilities of alkali metal-doped C6O6Li6 organometallics are analyzed via density functional theory methods. The thermal stability of the considered complexes is examined through interaction energy (Eint) calculations. Doping of alkali metal derives diffuse excess electrons, which generate the electride characteristics in the respective systems (electrons@complexant, e-@M@C6O6Li6, M = Li, Na, and K). The electronic density shifting is also supported by natural bond orbital charge analysis. These electrides are further investigated for their nonlinear optical (NLO) responses through static and dynamic hyperpolarizability analyses. The potassium-doped C6O6Li6 (K@C6O6Li6) complex has high values of second- (βtot = 2.9 × 105 au) and third-order NLO responses (γtot = 1.6 × 108 au) along with a high refractive index at 1064 nm, indicating that the NLO response of the corresponding complex increases at a higher wavelength. UV-vis absorption analysis is used to confirm the electronic excitations, which occur from the metal toward C6O6Li6. We assume that these newly designed organometallic electrides can be used in optical and optoelectronic fields for achieving better second-harmonic-generation-based NLO materials.

In the present investigation, quantum chemical calculations have been performed in a systematic way to explore the optoelectronic, charge transfer, and nonlinear optical (NLO) properties of different bis(dicyanomethylene) end-functionalized quinoidal oligothiophenes. The effect of different conformations (linking modes of thiophene rings) on conformational, optoelectronic, and NLO properties are studied from the best-performed dimer to octamer. The optical and NLO properties of all the selected systems (1–7) are calculated by means of density functional theory (DFT) methods. Among all the designed compounds, the largest linear isotropic (αiso) polarizability value of 603.1 × 10–24 esu is shown by compound 7 which is ∼12, ∼16, ∼9, ∼11, ∼10, and ∼4 times larger as compared to compounds 1–6, respectively. A relative investigation is performed considering the expansion in third-order NLO polarizability as a function of size and conformational modes. Among all the investigated systems, system 7 shows the highest value of static second hyperpolarizability ⟨γ⟩ with an amplitude of 7607 × 10–36 esu at the M06/6-311G** level of theory, which is ∼521, ∼505, ∼38, ∼884, ∼185, and ∼15 times more than that of compounds 1–6, respectively. The extensively larger ⟨γ⟩ amplitude of compound 7 with higher oscillator strength and lower transition energy indicates that NLO properties are remarkably dependent upon linking modes of thiophene rings and its chain length. Furthermore, to trace the origin of higher nonlinearities, TD-DFT calculations are also performed at the same TD-M06/6-311G** level of theory. Additionally, a comprehensive understanding of the effect of structure/property relationship on the NLO polarizabilities of these investigated quinoidal oligothiophenes is obtained through the inspection of Frontier molecular orbitals, the density of states (TDOS and PDOS), and molecular electrostatic potential diagrams including the transition density matrix. Hence, the current examination will not just feature the NLO capability of entitled compounds yet additionally incite the interest of experimentalists to adequately modify the structure of these oligothiophenes for efficient optical and NLO applications.

Complex [Cu(phen)2Cl]Cl∙2PABA∙4H2O has been isolated, where phen ligand is 1,10-phenanthroline and PABA is p-aminobenzoic acid. The complex crystallizes in the centrosymetric (monoclinic) space group P2(1)/n. The unit cell dimensions are a = 10.479(4) A, b = 22.396(7) A, and c = 16.212(6) A. The basic unit structure of complex is distorted trigonal bipyramidal. Two hydrogen-bonded PABA molecules are enclosed through π−π interactions in filled aryl box FAB motif made by juxtaposition of four phen from two opposing cations. While π−π interaction between phen causes the formation of offset face-to-face overlap OFF primary motif. The result is formation of extended (OFF-FAB)n chains. Cyclic voltammetry showed one reversible oxidation reduction process followed by one irreversible oxidation process. Thermal analysis indicated successive loss of crystalline water and crystalline PABA molecules, chloride ions, and phen ligands. DFT study indicates that PABA interacts with phen with binding energy 68.87 kJ mol−1 reflecting strong π-stacking. The charge density in HOMO is localized on the metal halogen bond, whereas in LUMO, it is spread over two phen. The vibrational spectrum of complex was calculated at M05-2X/6-31G(d) and compared with the experimental vibrational spectrum data. The inhibitory concentrations IC50 against carcinoma cells A549 (lung adenocarcinoma) and MDA-MB-231 (breast adenocarcinoma) are 3.4 and 4.5 µM, respectively. IC50 values of new complex are comparable to those of cisplatin and smaller than the values for [Cu(phen)2Cl]Cl∙6.5H2O.

DFT calculations are carried out to investigate nonlinear optical (NLO) properties of superhalogen (BCl4) and superalkali (NLi4) doped graphitic carbon nitride (GCN). It is noted that the geometries of doped GCN are sufficiently stable. The energy gap for GCN is 3.89 and it reduces to 0.53 eV in our designed molecule G4. Change in the dipole and transition dipole moment is observed along with small transition energies which are responsible for higher hyperpolarizabilities. Doped GCN has larger first and second hyperpolarizabilities which are basic requirements for NLO response. The second hyperpolarizability of GCN enhances from 1.59 × 104 to 2.53 × 108 au when doping with BCl4 and NLi4. TD-DFT calculations show the absorption maxima of doped GCN range from 700 nm to 1350 nm. EDDM analysis provides information on electronic distribution from excited to ground state. All these consequences show doped GCN can be a promising NLO material.

Herein, the structural, electronic, thermodynamic, linear and nonlinear optical properties of inorganic electrides, generated by alkali metal doping in group II–VI Ca12O12 fullerene, are studied. Endohedral doping of alkali metal leads to the formation of electrides whereas no such phenomenon is seen for exohedral doping. The electride nature of the endohedral fullerenes is confirmed through the analysis of frontier molecular orbitals. The results show that doping of alkali metal atoms leads to a reduction of the HOMO–LUMO gap and increase of the dipole moment, polarizability and hyperpolarizability of nanocages. Doping causes shifting of electrons from alkali metal atoms towards the Ca12O12 nanocage, which serve as excess electrons. Furthermore, the participation of excess electrons for enhancing the NLO response of these nanocages has been confirmed through the calculation of hyperpolarizability (βo). For exploring the controlling factors of hyperpolarizability, a two level model has been employed and the direct relation of hyperpolarizability with Δμ & fo, while an inverse relation of hyperpolarizability with ΔE has been studied. The electrides possess remarkable nonlinear response where the highest hyperpolarizability can reach up to 1.0 × 106 a.u. for endo-K@Ca12O12. This electride has the lowest ΔE of 0.63 eV among all compounds studied here. These intriguing results will be expedient for promoting the potential applications of the Ca12O12-based nano systems in high-performance nonlinear optical (NLO) materials.

In this study, the nonlinear optical (NLO) response of alkali metal atom (Li, Na and K) and their corresponding superalkali (Li3O, Na3O and K3O) doped six membered cyclic thiophene (6CT) has been explored. The optimized geometries of complexes; Li@6CT, Na@6CT, K@6CT, Li3O@6CT, Na3O@6CT and K3O@6CT depict that the superalkalis and alkali metals interact through the active cavity of 6CT. Interaction energies reveal that superalkalis have higher interaction with 6CT than alkali metals. The nonlinear optical (NLO) response of the reported complexes is estimated via both static and dynamic hyperpolarizabilities which are further rationalized by the HOMO–LUMO gap, natural bond orbital (NBO) charge transfer, dipole moment, polarizabilities and βvec. A remarkably high NLO response is computed for Na3O@6CT among all of the complexes. The static hyperpolarizability of the Na3O@6CT complex is 5 × 104 au along with the highest βvec value (2.5 × 104 au). High charge transfer (1.53e−) and small EH–L gap (2.96 eV) is responsible for such a large NLO response. For dynamic NLO responses, electro-optic Pockel's effect (EOPE) and second-harmonic generation (SHG) are explored. A very large quadratic nonlinear optical response (3.8 × 10−12 au) is observed for the Na3O@6CT complex. Moreover, the absorption spectrum of the Na3O@6CT complex shows ultra-high transparency in the ultraviolet and visible regions unlike any other of its counterparts.

Gas sensing materials have been widely explored recently owing to their versatile environmental and agriculture monitoring applications. Phosgene (COCl2) is a toxic and harmful gas, therefore, a reliable and sensitive technique is required for monitoring its quantity in the atmosphere. In this study, pure as well as copper decorated B[Formula: see text]P[Formula: see text](Cu-BP) nanoclusters were analyzed using DFT method to investigate their specific potential for phosgene gas adsorption. Cu interaction resulted in three optimized geometries S1, S2 and S3 with interaction energies of [Formula: see text]234.52[Formula: see text]kJ/mol, [Formula: see text]214.59[Formula: see text]kJ/mol and [Formula: see text]266.45[Formula: see text]kJ/mol, respectively. In all these three cases, the COCl2prefers to interact at the top of the cage. The phosgene molecule (COCl2) interacts with bare nanocage at a distance of 3.22[Formula: see text]Å with interaction energy of [Formula: see text]6.22[Formula: see text]kJ/mol, while the observed interaction energies of phosgene at Cu decorated B[Formula: see text]P[Formula: see text] are [Formula: see text]76.90[Formula: see text]kJ/mol, [Formula: see text]119.03[Formula: see text]kJ/mol and [Formula: see text]29.60[Formula: see text]kJ/mol, respectively. To observe the variations in electronic structure, fermi level, molecular electrostatic potential (MEP), frontier molecular orbitals (FMOs), natural bonding orbital ([Formula: see text]), softness, hardness, chemical potential and electrophilicity are calculated before and after phosgene adsorption. Energy gap reduce significantly after phosgene adsorption from 2.31[Formula: see text]eV, 2.05[Formula: see text]eV and 2.46[Formula: see text]eV to 1.54[Formula: see text]eV, 1.57[Formula: see text]eV and 2.45[Formula: see text]eV, respectively. Results of all analysis suggested that decoration of Cu significantly enhanced the adsorption power of B[Formula: see text]P[Formula: see text] nan-cluster for COCl2molecule. Therefore, the Cu-decorated B[Formula: see text]P[Formula: see text] nanocages are considered as potential candidates for application in COCl2sensors.

Four new metal carboxylates with o-nitro- and o-methoxyphenylacetic acid were synthesized and well characterized using single-crystal XRD. The synthesized complexes were evaluated for their biological potentials (antibacterial, antifungal, antioxidant, and enzyme inhibition) according to reported methods. Four bacterial and two fungal strains were targeted in this study and it was concluded that the synthesized compounds showed activities comparable to standard drugs. Co complex of nitro and tin complex of methoxy substituent are more active against bacterial as well as fungal strains. Enzyme inhibition activity of the synthesized compound was evaluated against acetylcholine esterase, butyrylcholine esterase, and trypsin. The maximum activity was depicted by Co complex of nitro, while all other tested compounds had moderate to good activity. DFT calculations were performed to gain further insight into the spectral properties. Docking model was also used to check the interaction of most active compound on the active site of the enzyme. All theoretical parameters supported the practical calculation and our findings that such compounds may be the best molecules in the near future against infectious as well as Alzheimer disease.

Nanostructured gas sensors find diverse applications in environmental and agricultural monitoring. Herein, adsorption of phosgene (COCl2) on pure and copper-decorated B12N12 (Cu–BN) is analyzed through density functional theory (DFT) calculations. Adsorption of copper on B12N12 results in two optimized geometries, named Cu@b66 and Cu@b64, with adsorption energies of −193.81 and −198.45 kJ/mol, respectively. The adsorption/interaction energies of COCl2 on pure BN nanocages are −9.30, −6.90, and −3.70 kJ/mol in G1, G2, and G3 geometries, respectively, whereas the interaction energies of COCl2 on copper-decorated BN are −1.66 and −16.95 kJ/mol for B1 and B2, respectively. To examine the changes in the properties of pure and Cu–BN nanocages, geometric parameters, dipole moment, QNBO, frontier molecular orbitals, and partial density of states (PDOS) are analyzed to comprehensively illustrate the interaction mechanism. The results of these parameters reveal that COCl2 binds more strongly onto copper-doped BN nanocages. Moreover, a higher charge separation is observed in COCl2–Cu–BN geometries as compared to copper-decorated BN geometries. Therefore, these nanocages may be considered as potential candidates for application in phosgene sensors.

The geometric, thermodynamic and electronic properties of Pd–graphene nanocomposites are comprehensively studied through quantum mechanical methods. Geometries of these clusters are optimized with the well-calibrated Minnesota functional M06-2X. The adsorption energies calculated at the M06-2X/LANL2DZ level show better agreement with those calculated from MP2/ANO-RCC-VDZP. Two different representative models for graphene, coronene and hexabenzocoronene, are used. The adsorption energies analysis reveals that the interaction energies increase with the size of the adsorbed cluster. However, for Pdn/hexabenzocoronene, the interaction energies show a sudden drop at Pd8/hexabenzocoronene. The difference in behavior between the interaction energies of Pdn/hexabenzocoronene and Pdn/coronene is attributed to the edge effect present in coronene. The electronic properties, including highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), Fermi level, molecular electrostatic potential (MEP), dipole moment, vertical ionization potential (VIP), vertical electron affinity (VEA), chemical hardness (η), softness (S) and chemical potential (μ) are studied. The VIP and VEA reveal that Pdn/coronene clusters are stable in nature with the least reactivity. The HOMO–LUMO energy gaps are reduced with the increase in cluster size. The electronic properties show irregular trends, where the most favorable electronic properties are obtained for Pd7/coronene and Pd10/coronene.

Nitro-explosives are a severe threat to the environment; therefore, detection and removal of nitro-explosives is the need of time. Herein, we illustrate the application of a newly discovered C2N surface for electrochemical detection and removal of nitro-explosives: namely, picric acid (PA), ethyleneglycoldinitrate (EGDN), and dimethyldinitrobutane (DMNB). Among the studied analytes, the highest adsorption energy of −25.12 kcal mol−1 (BSSE = −18.48 kcal mol−1) was observed for the PA@C2N complex. The nature of interactions was further quantified by SAPT0, NCI and QTAIM analyses, while the electronic properties were studied through EDD, NBO and FMO analyses. The SAPT0 analysis reveal that the dispersion factor remained dominant (60–64%) for stabilization of analyte@C2N complexes. The highest charge transfer was observed for PA@C2N (0.01e−), whereas the least amount of charge transfer was calculated for DMNB@C2N (−0.004e−). A more pronounced change in the EH–L gap was observed for PA@C2N (3.07 eV) compared to the DMNB@C2N (3.66 eV) and EGDN@C2N complexes (3.68 eV). It was noticed that a potential decrease in the EH–L gaps can be observed when the electronic transition occurs from the analyte to the C2N surface. The recovery time of PA is 35 s (298 K), which shows that the sensor can be easily recovered under ambient conditions. The results of various parameters reveal that C2N is more selective towards PA than toward the other studied analytes.

Graphene/polythiophene composites are widely used in a variety of optoelectronic devices and applications, e.g., as electrode materials in capacitors and solar cells, but the detailed molecular-lev...

Photoswitchable catalysis involves changes in properties of a catalyst based on difference in electronic and steric factors. These changes can selectively turn “ON” and “OFF” the catalytic activity by an external stimulus, light. Herein, we report dithienylethene based photoswitchable frustrated Lewis pairs for facile hydrogen recombination. The diarylethene moiety is not serving as template to alter the catalytic activity rather it is the core part of the catalyst. The rational design principle involves study of proton and hydride affinities of Lewis acid and base functionalities installed on the diarylethene photoswitch pair. Proton and hydride affinities differ significantly between open and closed isomers that help in designing an active molecule for hydrogen recombination. The proton and hydride affinities are then utilized to formulate best relative positions of Lewis acid and base on a single molecule in order to liberate one H2 molecule per photochrome. Energy barriers for hydrogen recombination are calculated for open and closed isomers. The closed isomer releases the hydrogen with a low activation barrier of 1.9 kcal mol−1 whereas the open isomer requires relatively high barrier of 4.7 kcal mol−1. The pronounced differences in energy barrier illustrate the potential of photoswitchable hydrogen recombination with diarylethene photochrome. The chemically stored hydrogen in frustrated Lewis pairs can be liberated in a controlled fashion through external stimulus for catalytic hydrogenation reactions. The present study will provide new dimensions to the scientific community for exploration of other systems with even better selectivities.

Based on DFT calculations, we designed a new series of superalkali doped graphdiyne (GDY) complexes, M2X@GDY (M = Li, Na, K and X = F, Cl, Br) having electron donor and acceptor (D-π-A) framework. Our results of interaction energies reveal that these superalkalis are quite stable and chemisorbed over the 18 membered site of GDY. DFT results also reveal that the doping of superalkalis on GDY leads to narrowing of the HOMO-LUMO gaps, which enhance their conductance properties. Furthermore, the polarizability and first hyperpolarizability of GDY are enhanced dramatically up to 7.7 × 104 au. The enhanced first hyperpolarizabilities are further explained by two level model expression from TD-DFT calculations. The TD-DFT results show that all these designed superalkali doped graphdiyne complexes have ultraviolet light transparency. To rationalize the hyperpolarizability trend in superalkali doped GDY complexes, βvec calculations are also performed. This study may provide better understanding for the direct synthesis of new GDY based NLO materials in industries.

Herein, we report the synthesis, characterization and biological evaluations of two novel organotin(IV) carboxylates (1 and 2). The structures of both complexes are confirmed by single crystal X-rays diffraction analysis. Density functional theory (DFT) studies are also executed to compare experimental (X-ray as well as spectroscopic) results with theoretical ones. Excellent correlation is observed between theoretical and experimental results. Furthermore, organotin(IV) carboxylates are evaluated against different bacterial stains (E. coli, S. aureus, K. pneumoniae and B. subtilis) and fungal stains (F. solani, A. fumigatus and A. niger). The complex 1 shows good antibacterial activity against B. subtilis (17 ± 0.32 mm), whereas complex 2 shows good antibacterial activity against E. coli (18 ± 0.41 mm) and B. subtilis (18 ± 0.41 mm). The complex 1 shows significant activity against A. fumigatus (28 ± 0.45 mm) and 2 shows good activity against A. fumigatus (16 ± 0.37 mm). To determine the interaction of organotin(IV) carboxylates with DNA, the interaction studies with salmon sperm DNA (SS-DNA) are also carried out through UV–vis absorption spectroscopy. The Gibbs free energies (ΔG) (−28.02 kJ/mol for complex 1 and -28.43 kJ/mol for complex 2) and high values of binding constants (K) (8.15 × 104 M−1 for complex 1 and 9.62 × 104 M−1 for complex 2) indicate that strong interactions are developed between organotin(IV) carboxylates and SS-DNA.

Continuous strides are being made to explore non-fullerene acceptors for organic solar cells. Here, optoelectronic properties of four new acceptor-donor-acceptor (A-D-A) type non-fullerene acceptor molecules are evaluated for their potential use in organic solar cells. The designed molecules contain indacenodithiophene (IDT) donor core connected with various acceptor groups through benzothiadiazole (BT) bridge unit. The designed molecules differ from each other in end-capped acceptor groups. The end-capped acceptors are 2-methylene-3-oxo-2,3-dihydroinden-1-ylidene) malononitrile (M1), 2,5,6-difluoro-2-methylene-3-oxo-2,3-dihydroinden-1-ylidene) malononitrile (M2), 2-methylene-2-H-indene-1,3-dione (M3), and 2,5-methylene-6-oxo-5,6-dihydrocyclopenta-c-thiphen-4-ylidene-malononitrile (M4). The optoelectronic properties are evaluated in comparison with the recently reported R which is structurally similar to the designed molecules. The reference compound R contains indacenodithiophene (IDT) donor core unit with 3-ethyl-d-ethylidene-2-thioxothiazolidin-4-one end capped acceptor group. The A-D-A acceptor molecules evaluated here exhibit proper frontier molecular orbital diagram to facilitate the charge mobility. M2, containing 2-(5,6-difluoro-2-methylene-3-oxo-2,3-dihydroinden-1-ylidene) malononitrile end-capped acceptor group, exhibits maximum absorption at 805 nm which is attributed to extended conjugation with the BT unit. Results of transition density matrix (TDM) show clear effect of end caped acceptor group on electro-hole exciton. Small coupling of electron and hole in M4 illustrates easy dissociation of exciton as compared with other molecules. Among all, M4 shows the highest hole transfer rate as revealed from low hole reorganization energy (λh). The open circuit voltage (Voc) of reference R is 1.96 V with donor polymer PTB7-Th while the designed molecule M3 exhibits the Voc of 2.02 V. Hence, the designed fullerene free acceptor molecules are suitable for transparent organic solar cells.

Design and synthesis of high energy density materials is an escalating area of research. Continuous strides are made to explore new and better materials for this purpose. Herein, we report a new and effective strategy to improve the cell voltage and performance of Na-ion batteries where phosphide nanoclusters are doped with endohedral halides. Bare and halide doped boron and aluminum phosphides (BP and AlP) are studied for their applications as electrodes (anodes) in Na-ion batteries. The geometric and electrochemical properties of Na/Na+ with both B12P12 and Al12P12 nanocages are investigated. The interaction energies (Eint.) and frontier molecular orbitals (FMOs) of Na/Na+ ion with B12P12 and Al12P12 nanocages are studied to investigate the effect of neutral or ionic Na on the geometric and electrochemical properties. Bare AlP and BP offer cell voltages of 0.56 and 0.61 V, mainly due to small differences in the interaction energies of Na and Na+ bound systems. The cell voltage is significantly improved by encapsulation of different halide ions into B12P12 and Al12P12 nanocages. Change in Gibbs free energy is significantly improved by the encapsulation of F− into B12P12 and Al12P12 among all considered halides, which results in increase in cell voltage up to 4.5 and 3.5 V for endo-F@B12P12 and endo-F@Al12P12, respectively. This value is higher as compare to cell voltage estimated for carbon nanotubes, functionalized BN nanosheets and B40 fullerenes. The cell voltage of 4.5 V is the highest for any such system. The results here are helpful in designing new materials with even better energy storage density.

Photoswitchable catalysis involves alteration in the intrinsic catalytic properties of an active species through a reversible photochemical transformation. Herein, we report dihydroazulene-vinylheptafulvene (DHA-VHF) based photoswitchable frustrated Lewis pairs (FLPs) for reversible hydrogen activation. The dihydroazulene-vinylheptafulvene moieties here do not act as template to control the catalytic activity, rather the core part of the catalyst. The rational design principle involves evaluation of proton and hydride affinities of Lewis acids (borane) and base (phosphine and amine) functionalities installed on dihydroazulene-vinylheptafulvene photoswitch pair. Significant differences are observed between open VHF and closed DHA for proton and hydride affinities, and these differences are explained by geometric and electronic factors. The individual proton and hydride affinities are utilized to logically formulate best relative positions of both Lewis acid and base on a single molecule in order to activate one H2 molecule per photochrome. For our judiciously designed FLPs, the behavior of phosphine based FLP resembles to that of amine based FLPs at position 2 and 3, however they differ at position 8a. For amine based FLP, the energy released for hydrogen splitting is higher than DHA for all positions (2, 3, 8a) whereas in VHF phosphine based FLP, the energy released on H2 splitting in VHF is lower than that of DHA at position 8a. Moreover, hydrogen splitting is studied on couple of cautiously selected molecules based on the proton and hydride affinities. The activation barriers for hydrogen splitting in VHFs are about 8–10 kcal mol−1 lower than the corresponding barriers in DHAs, chiefly due to the higher hydride and proton affinities.

Due to limitations of fullerene based acceptor molecules for solar cell applications, research is recently diverted to explore non-fullerene acceptor molecules. In this regard, four new A-D-A type fused ring electron acceptor molecules (M1, M2, M3 and M4) are evaluated for their opto-electronic properties for transparent organic solar cells. These molecules contain strong electron donor undecacyclic linked with four different acceptor moieties, 2-(3-ethly-5-methylene-4-oxothiazolidin-2-yluidene)malononitrile (M1), 2-(5,6-dicyano-2-methylene-3-oxo -2,3-dihydroindene-1-ylidene)malononitrile (M2), 2-(5-methylene-6-oxo-tetrahydro-1H-cyclopenta-thiophene-4(5H)-ylidene)malononitrile (M3), and 3-ethyl-5-methylene-2-thioxothiazolidin-4-one (M4). The electronic and optical properties of these molecules are compared with the reference molecule R, which is recently reported as excellent non-fullerene based acceptor molecule. Among all molecules, M2 exhibits the maximum red shift where absorption appears 893.5 nm with B3LYP/6-31++G(d,p) level of theory due to highly extended conjugation between electron withdrawing end-capped acceptor moieties. The calculated Open circuit voltage (Voc) of reference molecule R is 1.78 eV with donor polymer PTB7-Th while molecule M2 exhibits the Voc value of 1.86 eV.

Spectroscopic studies-based on 1D (1H NMR, 13C NMR), 2D-NMR (COSY, HMBC, HSQC), UV–visible, FTIR techniques and quantum chemical studies established on the density functional theory (DFT) were carried out for the natural withanolide glycosides, isolated from Withania Coagulans Dunal. The new glycoside withanolide named as (20R,22R)-14α,17,20β,27-trihydroxy-1-oxowitha-5,24-dienolide-27β-(O-β- d -glucopyranoside) (1), and a known withanolide (20R,22R)-14α-20β,27-trihydroxy-1-oxowitha-5,24-dienolide-3β-(O-β- d -glucopyranoside) (2) are reported here from W. coagulans. The molecular mass of these compounds were confirmed through Fast Atom Bombardment Mass Spectrometry (FAB-MS). Geometric and spectroscopic detailed were obtained from DFT calculations. 1H and 13C NMR theoretical values were found a little higher than the experimental values, but the trend in the chemical shift correlates well with the experimental values. The RMSD values of 1H and 13C NMR of 1 and 2 were 0.4 and 0.38, and 4.94 and 5.02 respectively. The calculated band gap was found 4.93 and 5.00 eV for 1 and 2 respectively which indicated the stable nature of these compounds towards redox reactions.

Alkene is an attractive substrate for chemists due to its easy availability and reactivity towards large number of reactants affording diverse range of organic compounds. It reacts under ionic and free radical mechanisms including single electron transfer (SET). In this review, strategies used for C–C and C-heteroatom functionalization of alkene has been discussed with emphasis on the regio, stereoselectivity, mechanistic detail and sustainability aspects. These strategies mainly follow the free radical mechanism, and the highly reactive carbon radicals show uncontrollable regio- and stereoselectivities. Thus these strategies still need to be focused; especially in the asymmetric versions. The regio- and stereoselectivities of functionalization of alkenes have been highlighted and debated. In addition, the hazardous reagents such as Cl2, Br2 I2, CO, peroxides, and benzene have also been discussed with the emphasis on their impact on the environment. Their plausible green alternatives have also been suggested, such as MX as halogen replacement; CO surrogates (formaldehyde etc.); sustainable aromatic solvents as benzene replacement. The non-green strategies relying on pre-formed silyl hydride and their green alternative strategies such as transfer hydrogenations have also been indicated. The applications of the functionalization of alkenes for the total synthesis of bioactive compounds have also been discussed in detail. In addition, future perspectives are also highlighted for further developments in the functionalization of alkenes.

The low concentration of graphene (

In this study, the nonlinear optical (NLO) properties of pristine phosphorene and superalkali (Li3O) doped phosphorene are estimated through the density functional theory (DFT) method to investigate the optical properties. The geometries of complexes have been optimized using the B3LYP/6-31G (d, p) level of theory. The effects of doping on phosphorene have been thoroughly explained by vertical ionization energy (VIE), interaction energies (Eint), and natural bond orbitals (NBO), Moreover, the density of states (DOS), electron density difference map (EDDM) analysis, the frontier molecular orbitals (FMO) plots are also given out to find more physical divination into the electronic communication and structure property relationship. The doping of superalkali conclusively has reduced the HOMO-LUMO energy gap of M1 3.28 eV–1.25 eV for M2 making it the n-type semiconductor. The higher values of Eint, Efm and VIE obtained for M2 has indicated that this complex has higher stability and stronger interaction between superalkalis and phosphorene. More interestingly, there has been a gradual increase in the first static hyperpolarizability (βstatic) values for M1, M2 and M3 are 115.75 au, 4118.6 au, and 659.30 au respectively. The Static second hyperpolarizability (γstatic) of the doped complexes has also been calculated from which the M2 has the highest value of 1382.5 ҳ 103 au. The TD-DFT exploration has exhibited that the doped molecules are adequately transparent in the UV region. Some selected systems are also compared with the p-NA reference molecule which is a familiar external reference molecule for NLO applications. From UV absorption analysis, it can be found that these doped complexes of phosphorene may be contemplated as a new applicant for intense ultraviolet NLO materials. Computational studies have revealed the stability of M2 and M3 making them feasible as NLO materials in optoelectronic applications.

Nonlinear optical materials possess high rank in fields of optics owing to their impacts, utilization and extended applications in industrial sector. Therefore, design of molecular systems with high nonlinear optical response along with high thermodynamic stability is a dire need of this era. Hence, the present study involves investigation of bi-alkali metal doped boron phosphide nanocages M2@B12P12 (M = Li, Na, K) in search of stable nonlinear optical materials. The investigation includes execution of geometrical and opto-electronic properties of complexes by means of density functional theory (DFT) computations. Bi-doped alkali metal atoms introduce excess of electrons in the host B12P12 nanocage. These electrons contribute towards the formation of new HOMO, thus reducing HOMO-LUMO gaps. The reduced HOMO-LUMO gap ranges from 0.63eV to 3.69eV. The diffused excess electrons also come up with increased hyperpolarizability values of complexes i.e. up to 4.0×104au. TD-DFT calculations have been performed to examine crucial transition states and for UV-VIS analysis. IR and DOS spectra have been plotted to support our obtained results. Non covalent interaction (NCI) calculations along with quantum theory of the atoms in molecules (QTAIM) analysis were carried out to understand the bonding interactions between alkali metal atoms and B12P12 nanocage. All obtained results suggest bi-alkali metal doped nanocages as exceptionally stable materials with improved NLO response and superb candidates for their vast applications in optics.

In the current study, for the first time; the drug loading efficacy of graphitic‑carbon nitride (g-C3N4) for an anticancer drug, cisplatin was evaluated. To explore the effectiveness of g-C3N4 as a drug-delivery system, some important properties of cisplatin drug, g-C3N4 carrier, and g-C3N4-cisplatin complex were calculated at ground state and excited state. The cisplatin drug prefers to interact via H atoms to the N atoms of g-C3N4 carrier with an adsorption energy of about −1.25 eV. The type of interactions between g-C3N4 carrier molecule and cisplatin drug are visualized with the help of non-covalent interaction (NCI) analysis which demonstrated the presence of weak non-covalent interactions. These weak interactions between cisplatin drug and g-C3N4 carrier play a key role in drug-offloading at the target site. The charge-transfer process was studied with the help of HOMO-LUMO analysis and further supported by charge-decomposition analysis (CDA). Furthermore, excited-state calculations for g-C3N4-cisplatin complex revealed that λmax is red-shifted by 154 nm in the gaseous phase, and the inclusion of water results in the blue shift of λmax. Interestingly, by comparing theoretical and experimental spectra, it was found that our theoretical spectra in the solvent phase are in close agreement with experimental results. The photoinduced electron-transfer (PET) process and its effect on fluorescence phenomena, was investigated for different excited-states of g-C3N4-cisplatin complex with the help of electron-hole theory. Moreover, g-C3N4 with +1 and − 1 charge state shows negligible structural distortion and it also gives stable complexes with cisplatin drug. Overall the findings suggest that g-C3N4 could be used as an efficient drug-delivery system for the cisplatin drug to treat various types of cancer.

In this study, the therapeutic potential of phosphorene as a drug-delivery system for chlorambucil to treat cancer was evaluated. The geometric, electronic and excited state properties of chlorambucil, phosphorene and the phosphorene–chlorambucil complex were evaluated to explore the efficiency of phosphorene as a drug-delivery system. The nature of interaction between phosphorene and chlorambucil is illustrated through a non-covalent interaction (NCI) plot, which illustrated that weak forces of interaction are present between phosphorene and chlorambucil. These weak intermolecular forces are advantageous for an easy offloading of the drug at the target. Frontier molecular orbital analysis revealed that charge was transferred from chlorambucil to phosphorene during excitation from the HOMO to LUMO. The charge transfer was further supplemented by charge-decomposition analysis (CDA). Excited-state calculations showed that the λmax was red-shifted by 79 nm for the phosphorene–chlorambucil complexes. The photo-induced electron-transfer (PET) process was observed for different excited states, which could be well explained visually based on the electron–hole theory. The photo-induced electron transfer suggests that a quenching of fluorescence occurs upon interaction. This study confirmed that phosphorene possesses significant therapeutic potential as a drug-delivery system for chlorambucil to treat cancer. This study will also motivate further exploration of other 2D materials for drug-delivery applications.

Three series of compounds Li2F@B12P12, Li3O@B12P12 and Li4N@B12P12 are theoretically designed and investigated for their nonlinear optical response using density functional theory (DFT). Computational results reveal that isomers VIII and X are inorganic electrides whereas the others are excess electron systems. Interaction energies reveal that these systems are quite stable and superalkalis are chemisorbed on the nanocage. Doping of a B12P12 nanocage with superalkali brings a considerable increase in the first hyperpolarizability response of the system. The highest first hyperpolarizability (β0 = 3.48 × 105 a.u.) along with good ultraviolet transparency is observed for isomer III of Li2F@B12P12. Moreover, all three series of compounds are systemically studied for the effect of different superalkalis and different doping positions on the nonlinear optical response. This study will be advantageous for promoting the potential applications of the fullerene-like superalkali doped B12P12 nanostructures in new types of electronic nanodevices and high-performance nonlinear optical materials with good ultraviolet transparency.

Non-fullerene small acceptor molecules have gained significant attention for application in organic solar cells owing to their advantages over fullerene based acceptors. Efforts are continuously being made to design novel acceptors with greater efficiencies. Here, optoelectronic properties of four novel acceptor–donor–acceptor (A–D–A) type small molecules (A1, A2, A3 and A4) were studied for their applications in organic solar cells. These molecules contain an indacenodithiophene central core unit joined to different end capped acceptors through a monofluoro substituted benzothiadiazole (FBT) donor acceptor (DA) bridge. The different end capped acceptor groups are; 2-2(2-ethylidene-5,6-difluoro-3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (A1), 2-2(2-ethylidene-3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (A2), 2-(5-ethylidene-6-oxo-5,6-dihydrocyclopenta-b-thiophene-4-ylidene)malononitrile (A3), and 2-2(2-ethylidene-5,6-dicyano-3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (A4). The calculated optoelectronic properties of the designed molecules were compared with a well-known reference compound R, which was recently synthesized and reported as being an excellent A–D–A type acceptor molecule. All designed molecules showed the appropriate frontier molecular orbital diagram for a charge transfer. A4 shows the highest absorption maximum (λmax) of 858.6 nm (in chloroform solvent), which was attributed to the strong electron withdrawing end-capped acceptor group. Among all of the designed molecules, A3 exhibits the highest open circuit voltages (Voc) which was (1.84 V) with PTB7-Th and (1.76 V) with the P3HT donor polymer. Owing to a lower value of λe with respect to λh, the designed molecules demonstrated superior electron mobilities when compared with reference R. Among all of the molecules, A4 shows the highest electron mobility owing to the lower value of λe compared to R.

We have developed novel formazan dyes (18–23) of enhanced fastness properties with cost-effectiveness in an aqueous system, without employing any Buffers and organic solvents. Their development was entailed of the synthesis of 2-((phenyl (2-(4-sulfophenyl) hydrazono) methyl) diazenyl) benzoic acid followed by the diazotization of 2-aminobenzoic acid that further reacted with the 4-[(2Z)-2-benzylidenehydrazinyl] benzene sulfonic acid. The multi-chromic (1:1 and 2:1) metal complexes of 2-((phenyl (2-(4-sulfophenyl) hydrazono) methyl) diazenyl) benzoic acid had been developed with the salts of Cr, Fe, Co, Cu and Ni; and they were characterized by elemental analysis, powder X-ray crystallography, Ultraviolet–visible, Fourier transforms infrared, Proton nuclear magnetic resonance and C13-nuclear magnetic resonance spectroscopic techniques. Density functional theory (DFT) studies of all dyes (18–23) were performed to evaluate the most stable geometries and structural parameters as well. The synthesized formazan dyes were evaluated for their different fastness (light, wash, perspiration), exhaustion and fixation properties on goat leather fabric and were revealed to have virtuous fastness properties (3–5, 4–5, 3–5, and 4–5) with high percentage value of exhaustion and fixation ranged from 91 to 97% and 90–98% respectively. The synthesized formazan dyes (18–23) were developed different colors such as Red, Brown, Green, Black, and Blue on leather. Synthesized formazan dyes were also evaluated for their antibacterial propensity on leather substrate and in solution by agar well diffusion method. The metal complex formazan dye (21) was demonstrated the significant bactericidal propensity against E. coli, S. aureus, Klebsiella and B. subtilis in solution and on leather by exhibiting maximum ZOIs (19 ± 0.05 mm, 25 ± 0.07 mm, 23 ± 0.09 mm, 27 ± 0.03 mm) and percentage reduction in bacterial growth (60 ± 0.03%, 69 ± 0.07%, 80 ± 0.05% and 86 ± 0.08%) respectively. Hence, newly synthesized formazan dyes (18–23) have efficient optical and antibacterial properties that would be proved valuable for the development of new industrial products to be commercialize.

Two carboxylate esters (methyl: (I) and ethyl: (II)) of 4-{(4-methylphenylsulfonamido)- methyl}cyclohexanecarboxylic acid (sulfonamide) were synthesized and characterized by FTIR and X-ray crystallography. DFT studies were conducted in order to optimize the structures using Gaussian software which confirmed the bond angels and bond lengths obtained from single crystal analysis. Both Compounds (I and II) were evaluated for their biological studies viz; antioxidant activity (DPPH), enzyme inhibition activity (esterase and proteases), antibacterial (Halomonas halophila, Halomonas salina, Shigella sonnei, Bacillus subtilis, Chromohalobacter salexigens, Chromohalobacter israelensis, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae) and anti-fungal (Aspergillus niger and Alternaria alternata). Results depicted that II is more active as compared to I in antioxidant and esterases while I is more potent against protease while moderate results were shown by both.

The sensing properties of 2D carbon materials are well explored for various gaseous analytes, however, the detection of toxic chemicals e.g., phosgene (Ph), thiophosgene (ThP) and phosogenoxime (PhO) are rarely studied. To the best of our literature survey, only a single study is found for the adsorption of phosgene on 2D carbon nanoflake (graphyne). This motivated us to explore the sensitivity of graphdiyne (GDY) nanoflake for the detection of phosgene and couple of its derivatives. Therefore, we have performed a density functional analysis to simulate the comparative interaction between phosgene, thiophosgene and phosogenoxime with graphdiyne nanoflake. The interaction behaviours are estimated by interaction energies, (symmetry adopted perturbation) SAPT0 analysis, (noncovalent interaction index) NCI analysis, molecular orbital analysis, natural bond orbital (NBO) charge transfer and UV–Vis absorption analysis. The obtained results demonstrate the trend in sensitivity of graphdiyne for analytes is PhO@GDY > ThP@GDY > Ph@GDY. The sensible justification for the particular observation is provided by the energy gaps between HOMO and LUMO orbitals in term of %sensitivity. The %sensitivity is in complete accord with the aforementioned trend. In addition, results suggest that graphdiyne based sensor for detecting phosgene and derivatives are better in sensitivity in comparison with already reported graphyne sensor.

The electrical and optical properties of superalkali (OLi3) and superhalogen (MgF3) doped boron nitride nanocage are investigated. Superalkali and superhalogen are doped physically and substitutionally with boron nitride and its geometrical and optoelectronic properties are analyzed and compared systematically. In the doped nanocage of boron nitride, the linear optical polarizability and nonlinear optical hyperpolarizability increases to a greater extent. The increasing trend of the hyperpolarizability in the nanocage of metal-doped boron nitride depends on the atomicity of superhalogen and superalkali metal. The energy bandgap of HOMO-LUMO also decreases due to the injection of new energy levels in all the doped compounds of boron nitride near the Fermi level. Among different combinations, MgF3 and OLi3 doped with B12N10 found the most reliable combination with enhanced linear and nonlinear optical polarizability. The current clue gives wide applications for boron nitride nanocage in electrical instruments and devices that play an important role in the designing of efficient nonlinear optical materials.

Exploring new nonlinear optical materials with excess electron character is extremely important for promoting the application of excess electron compounds in nonlinear optics. Herein, by using density functional theory (DFT) computations, new superalkali-based alkalides Li3O@[12-crown-4]M− are designed as excess electron compounds. QTAIM studies suggest that the complexant interacts with alkali and superalkali clusters through non-covalent interactions. These complexes are thermodynamically stable and their interaction energies range from −33.40 ∼ −44.23 kcal mol-1. The alkalide nature of these compounds is guaranteed by their HOMOs values and NBO charge analysis. Being excess electron compounds, these alkalides shows potential electronic properties. Their HOMO-LUMO gaps ranging from 0.17–0.27 eV. With excellent properties, these complexes show remarkable total hyperpolarizability (βo) response (9.30×104–5.26×106au). Interestingly, the hyperpolarizability response is dependent on the size of alkali metals. The βvec values are quite comparable to total hyperpolarizability at the same level of theory. Furthermore, the hyperpolarizability calculated through two-level model (βtl) values show a trend similar to hyperpolarizability. Additionally, the dynamic hyperpolarizability response for EOPE effects is much pronounced at the dispersion frequency of 532 nm. The second hyperpolarizability response for the dc-Kerr constant is increased up to 2.75 × 1012 au which is much higher than those of previously reported alkalides. Strikingly, the frequency-dependent NLO response shows dependence on alkalide character rather than the size of alkali metal (M). Moreover, the βHRS value is recorded up to 2.16 × 106 au. The significant dipolar contribution to hyperpolarizabilities Φβ(J = 1) are observed for these complexes.

Continuous strides are made to realize molecular systems with exceptionally high nonlinear optical response. Here, we report alkali metal exohedrally doped phosphide nanocages as the excellent materials with remarkable nonlinear optical response. Density functional theory calculations have been performed for geometric, diffusion kinetics, electronic, linear and nonlinear optical properties of exohedral alkali metal doped aluminum phosphide and boron phosphide (M@Al12P12 and M@B12P12) nanocages. All possible doping sites are evaluated for geometric, electronic, and nonlinear optical properties. The kinetic stabilities of the doped structures are evaluated through diffusion barriers. Adsorption energies revealed that all structures are thermodynamically very stable. Doping of alkali metal significantly influences the properties of nanocages. HOMO-LUMO (H-L) gap is reduced significantly whereas hyperpolarizability is increased several orders of magnitude. The dramatic change in HL gap is observed for Na@Ptop-Al12P12 whereas maximum hyperpolarizability is calculated for K@Ptop-B12P12. The H-L gap of Na@Ptop-Al12P12 is about 0.94 eV compared to 3.36 eV of pure AlP nanocage. Remarkably high hyperpolarizability of 7.9 × 105 au for K@Ptop-B12P12 is comparable to the highest reported hyperpolarizabilities in the literature. Furthermore, Al/Btop and Ptop doped nanocages show relatively higher hyperpolarizability values compared to other doped structures.

Five new Acceptor-Donor-Acceptor (A-D-A) type small donor molecules (M1-M5) namely; Dimethyl cyanoacetate terthiophene di(methylthiophene) dibenzosilole (DMCAO3TBS) (M1), Dimelononitrile terthiophene di(methylthiophene) dibenzosilole (DMCNTBS) (M2), Dimethyl rhodanine terthiophene di(methylthiophene) dibenzosilole (DMRTBS) (M3), Dimelanonitrile terthiophene di(methylthiophene) methyl carbazole (DMCNTCz) (M4) and Dimethyl rhodanine terthiophene di(methylthiophene) methyl carbazole (DMRTCz) (M5) were designed and theoretically explored their electronic, photophysical and geometrical properties via DFT best functional MPW1PW91/6-311G (d,p) with respect to reference molecules Dioctyl cyanoacetate terthiophene di(octylthiophene) dioctylfluorene (DCAO3TF) (Ra) and Dioctyl cyanoacetate terthiophene di(octylthiophene) octylcarbazole (DCAO3TCz) (Rb). Among the designed donor molecules (M1-M5), M2 and M4 represented lowest band gap value (2.480 eV and 2.47 eV) with distinctive broad absorption peak at 598 nm and 601 nm in chloroform. Theoretically estimated reorganization energies of these molecules recommended excellent property of charge mobility. The designed donor molecules (M1-M5), demonstrated lower λe value with reference to their λh, showing that these molecules could be ideal candidates for the transfer of electron while M2 and M4 were found to be best molecules having lowest λe (0.006 eV and 0.005 eV respectively). Additionally the Voc of M2 and M4 are 2.01 eV and 1.85 eV respectively with respect to PCBM.

Four new 3-(2-(3-Phenyl-5-substituted phenyl-4,5-dihydropyrazol-1-yl)thiazol-4-yl)-2H-chromen-2-one derivatives (1–4) were synthesized and fully characterized by spectroscopic techniques. The final structures of all chromenone analogues (1–4) were confirmed by single crystal X-ray diffraction analysis. Quantum chemical studies were performed to compare the results from the theoretical studies with the experimental (X-ray as well as spectroscopic) ones. The theoretically simulated geometric parameters and other spectroscopic properties agreed nicely with the experimental data. All compounds were evaluated for biological activity (acetyl cholinesterase inhibition potential). Compound 3 emerged as the most potent derivative in acetylcholine esterase (AChE) inhibition assay with IC50 = 27.29 μM. The IC50 of compound 3 is greater than the standard drug galantamine (IC50 = 44.02 μM). To rationalize the potencies, molecular docking studies were also carried out. These docking results revealed a good correlation between binding energies values and in vitro AChE inhibition assay.

Biaryls are the potential source of synthetic drugs. The present study describes the synthesis of a series of functionalized biphenyl derivatives (3a-3g) using Pd-catalyzed Suzuki coupling reaction. The experimental results revealed the facile synthesis of biphenyl derivatives (3a-3g) with notably high yield (80-88%). Density functional theory (DFT) studies were performed by Gaussian 09 software in order to rationalize the selectivity of coupling at C-Br bond instead of C-Cl bond. In addition of synthesis, the biological activities (biofilm inhibition, hemolytic and anti-thrombolytic) of these novel compounds were investigated. These results exhibited good biofilm inhibition (5.86-65.8%), hemolytic (1.32-30.1%) and anti-thrombolytic activities (9.64-42.5%), indicating the potential use of these compounds for pharmaceutical applications

Density functional calculations have been performed to study the diffusion behavior of various alkali metal atoms on the surface of (AlN)12 and (BN)12 nanocages. Alkali metal doped nanocages possess remarkable nonlinear optical response. A number of studies in the literature discuss the structural, electronic, nonlinear and sensor applications of pure and doped X12Y12 nanocages. Alkali metal atom doping at different adsorption sites is reported; however, the information regarding the interconversion barriers for the diffusion of alkali metals on these structures is still unknown. In this study, the barriers for the diffusion of alkali metal atoms (Li, Na, K) on these nanocages are studied at ωB97XD method. The barriers are obtained by scanning potential energy surface along the movement of alkali metals through the nanocage. The barriers for the diffusion of lithium atom on AlN nanocage are found to be higher than BN nanocage. The highest interconversion barrier calculated is 48.77 kcal mol−1 for b66 to r6 movement of lithium atom on AlN nanocage. The lowest migration barrier is observed for sodium movement from r6 to b66 in AlN nanocage.

In the present investigation, we employ a dual approach consisting of experimental and computational techniques to synthesise and characterise the Schiff-base including the moieties of nitrophenyl ...

In the present study, we have designed and synthesized a Schiff base derivative 3 and characterized by FT-IR, 1H and 13C NMR spectroscopy. Single crystal X-ray diffraction and NMR studies were also performed. The synthetic compound was screened for its inhibitory potential against carbonic anhydrase II. The experimental results were validated by molecular docking and dynamic simulations of compound 3 in the active pocket of enzyme. Important binding interactions with the key residues in the active site of the carbonic anhydrase enzyme were revealed. Moreover, supramolecular assembly of the title compound was analyzed by density functional theory (DFT) calculations. These studies rendered a more clear understanding for the demonstration of novel molecular mechanism involved in CA II inhibition by the synthesized compound.

A new series of bis((5-aryl-1,3,4-oxadiazol-2-yl)thio)alkanes 4–14 have been synthesized via nucleophilic substitution reaction of dihaloalkanes with respective 1,3,4-oxadiazole-2-thiols 3a-f, and characterized by spectroscopic techniques. The structures of 4 and 12 were unambiguously confirmed by single-crystal X-ray diffraction analysis. Density functional theory calculations at B3LYP/6-31 + G(d) level of theory were performed for comparison of X-ray geometric parameters, molecular electrostatic potential (MEP) and frontier molecular orbital analyses of synthesized compounds. MEP analysis revealed that these compounds are nucleophilic in nature. Frontier molecular orbitals (FMOs) analysis of 4–14 was performed for evaluation of kinetic stability. All synthesized compounds were screened in vitro for antimicrobial activity against three bacterial and three fungal strains and showed promising results.

Using DFT and DLPNO-CCSD(T) calculations, we explored electronic and energetic properties of F doped carbyne C10 ring to form C10F complex and its potential application as anode material in alkali-ion batteries. The adsorption of alkali metal (AM/AM+) is investigated on C10F complex. The adsorption free energies of K and K+ are –0.75 and –77.34 kcal mol−1, respectively which give rise to cell voltage (Vcell) of 3.32 V. The electrochemical cell volage for Li/Li + and Na/Na + are 3.12 V and 2.80 V, respectively. A large storage capacity of 579 mAh g−1 is achieved for all three studied LIBs, SIBs, and KIBs. These results present C10F complex as a promising anode material for alkali-ion batteries.

For designing better energy storage devices, the interfacial interaction between ILs and nanostructure is a prerequisite. In the present study, the interaction of ionic liquids such as [EMIm]+[X]− on Al12N12 and Al12P12 nanocages has been investigated using DFT theory. The complexes of Al12P12 nanocage exhibit higher values of adsorption energies than those of Al12N12. The adsorption energies of IL-complexes range from −38.9 to −63.6 kcal/mol. Non-covalent interaction (NCI) and quantum theory of atoms in molecules (QTAIM) analyses revealed non-covalent interactions between the ionic liquids and nanocages. NBO analysis shows charge transfer between the ionic liquids and Al12N12 and Al12P12 nanocages, which results in significant enhancement of dipole moment values of IL-complexes. [EMI]+ [X]−@Al12P12 complexes show higher dipole moment values than those of [EMI]+ [X]−@Al12N12 complexes. FMO analysis depicts a decrease in the HOMO-LUMO energy gap of IL-complexes, enhancing the electrical conductivity of these complexes. Furthermore, the calculated quantum molecular descriptors show that ILs adsorbed Al12N12 complexes are less reactive than ILs adsorbed Al12P12 nanocages. Thermodynamic properties revealed that the adsorption of ILs on Al12N12 and Al12P12 is an exothermic and spontaneous process. This study illustrates that the electronic properties of Al12N12 and Al12P12 nanocages are fine-tuned by the adsorption of ionic liquids. This study provides an efficient approach to design better electrode–electrolyte materials for super capacitors, fuel cells, ion batteries, and solar cells.

Herein, we report the theoretical insight into the adsorption mechanism of p-Aminophenol on graphene, silver cluster and silver graphene composites. DFT calculations are performed at M06-2X/LANL2DZ level of theory to explore the adsorption mechanism of p-Aminophenol (p-AP) over a bare coronene, a coplanar silver cluster (Ag6), and two isomers of silver-graphene composites (isomer 1 and isomer 2). The highest Eint is found in p-AP@Ag6 (−15.15 kcal mol−1) while the lowest is calculated for isomer 2 (−12.31 kcal mol−1). NCI results show that electrostatic forces have a strong influence on the stability of p-AP@Ag6 and also of isomer 1, which results in their higher stability. Additionally, MD simulations confirmed that the adsorption of p-Aminophenol over silver-graphene composite is stable and efficient at room temperature. The adsorption mechanism in these complexes is further explored through variations in; absorption maximum (λmax), excitation energies, and oscillator strength (fo). The values of Eint and shift of λ m a x decreases in the order p-AP@Ag6 > isomer 1 > p-AP@coronene ˃ isomer 2. NBO and CDA analysis are performed to gain a deeper insight into the direction and amount of charge transfer between donor and acceptor units. The degree of charge transfer as measured by the NBO charges decreases in the order isomer 1 > p-AP@Ag6 > isomer 2 > p-AP@coronene. The transfer of electron density from the analyte in the complexes is solely due to the contribution of the p-orbital in the HOMO. Orbital hybridization in the complexes results in the generation of new occupied and virtual energy states, and the appearance of new energy states close to the Fermi level causes a reduction in HOMO-LUMO gaps, and hence enhanced conductivity of p-Aminophenol complexes. The outcome of the current study will provide useful guidelines in the development of promising sensing material for p-Aminophenol.

Polypyrrole is experimentally reported as an excellent sensor for biological molecules including urea and uric acid. DFT calculations at M05-2X/6–31++G(d,p) are performed to gain theoretical insight into the sensing mechanism of polypyrrole for urea, uric acid, acetamide and sulfonamide. Geometry optimization and electronic property calculations have been performed on a series of oligopyrrole (1, 3, 5, 7 and 9) complexes, and the properties are extrapolated to infinite polymer through 2nd degree polynomial fit. Energy decomposition analyses (SAPT0) have been performed to demonstrate the contribution of electrostatic, induction, exchange and dispersion. The trend of SAPT0 interaction energies is very much comparable to that of binding energies. The noncovalent components of SAPT0 regularly increase with oligomer chain length; however, these components become almost constant after trimer for urea, acetamide, and sulfonamide. The increase in interaction and SAPT0 energies illustrate an increase in sensitivity of polypyrrole. Charge transfer and electronic properties also illustrate the high sensitivity of polypyrrole for uric acid. Energy difference between HOMO and LUMO orbitals of polypyrrole decreases upon doping with analytes. The decrease in the HOMO-LUMO gap shows an increase in the conductivity of polypyrrole. Our results indicate that polypyrrole has the highest sensing ability for uric acid, consistent with the experimental observations.