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Disulfide bond cleavage plays a crucial role in various chemical and biological processes. In recent years, developing novel and efficient catalysts for disulfide bond cleavage has garnered significant attention. This manuscript presents a comprehensive density functional theory (DFT) study on the separation of a disulfide bond by a well‐known Nona‐silicide Zintl cluster, Si94−. It is a single‐step exothermic reaction process that proceeds via the SN2 mechanism. This study also investigates the electronic activity, electron transfer process, and other electronic properties associated with the disulfide bond dissociation by the Si9‐Zintl cluster using the M06‐2X computational method. [ABSTRACT FROM AUTHOR]

The possible existence of nonagermanide deltahedral Zintl ion (Ge94−) as a nine-folded Lewis base is investigated from first principles calculations. It is observed that all nine centres, Ge94−, can make an adduct with Lewis acid. The presence of lone pairs is confirmed from the 1c–2e AdNDP calculation. It is further noticed that the bulky group functionalized organo-Zintl cluster, [Ge9(tBu)3]− , can potentially act as a Lewis base and can make an intermolecular frustrated Lewis pair (FLP) with a well-known Lewis acid Tris[2,4,6-tris(trifluoromethyl)phenyl] borane, [B{C6H2(CF3)3}3]. [ABSTRACT FROM AUTHOR]

The activation of the C-F bond in 1-fluorobutane, 1, 1-difluorobutane and 1, 1, 1-trifluorobutane by some frustrated Lewis pair (FLP) has been assessed by DFT based computational study. The FLPs are constructed from lutidine Lewis base in association with either B(C6F5)3 or Al(C6F5)3. Thermodynamics and kinetics of the reactions are studied, which reveals the concerning bond activation mediated by the Al(C6F5)3/lutidine FLP is more favourable than the analogous reactions mediated by the B(C6F5)3/lutidine pair. Therefore, the Al(C6F5)3 acid is superior to the B(C6F5)3 acid to construct an effective FLP for some unusual bond activation. The EDA-NOCV study together with the WBI calculation reveals the C-F bond activation in the studied systems takes place by the cooperative action of the FLP partners. The activation strain model reveals the strain energy of the reactants to reach the transition state (TS) rather than the interaction energy at the TS is the decisive factor to the TS barrier height of the concerned reactions. The activation of C-F bond in 1-fluorobutane, 1, 1-difluorobutane and 1, 1, 1-trifluorobutane by B(C6F5)3/lutidine and Al(C6F5)3/lutidine pairs has been assessed computationally. The Al(C6F5)3/lutidine pair is superior to the B(C6F5)3/lutidine pairs for such unusual bond activation as revealed by this study. [ABSTRACT FROM AUTHOR]

A triazole-bridged anthracene-sugar derivative 1 was designed and synthesized in one step. The sensing ability of 1 towards picric acid over other nitroaromatic compounds was established by absorbance and fluorescence spectroscopy in a water−acetonitrile medium (3 : 2, v/v). Furthermore, compound 1 could recognize Au(III) ions in 100% water among different metal species and anions. In the presence of picric acid, the receptor's fluorescence quenches within a minute. The Stern–Volmer quenching constants for picric acid and Au(III) ions were observed to be 1.59 × 105 and 1.8 × 105 M–1, respectively. Spectroscopic studies and density functional theory calculations supported the formation of the non-emissive charge transfer complex 1-picric acid after the interaction between 1 and picric acid. The probe showed a 1 : 1 binding mode for picric acid and Au(III) ions. The detection limits of 1 for picric acid and Au(III) were calculated to be 0.09 and 0.094 µM, respectively. Furthermore, receptor 1 has been effectively utilized to sense picric acid in river, pond, and tap water samples. Interestingly, it was found that the quenching process of 1 with picric acid is totally opposite to quenching with Au(III). [ABSTRACT FROM AUTHOR]

The study investigates the reactivity of a cyclic five‐membered intramolecular P/B frustrated Lewis pair towards acrolein through a cycloaddition reaction. Intrinsic reaction coordinate (IRC) calculations suggest the single‐step mechanism. It has been observed that the cycloaddition reaction occurs through a concerted mechanism in both the presence and absence of the catalyst. Analysis of reaction force and reaction electronic flux provides valuable information about the total work required and electronic activity along the IRC. Additionally, natural bonding orbital (NBO) analyses enrich the understanding of the mechanism in terms of the electron transfer process during the chemical reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • CAAC ligand stabilized boron dopped thiazolothiazoles molecules have positive electron affinity. • Six different boron dopped thiazolothiazoles have been designed. • Superhalogen property of these boron dopped thiazolothiazoles has been investigated. • They have good oxidizing property. The ab-initio calculation shows that nitrogen, boron, and sulfur (NBS) containing heterocyclic molecules, i.e., boron-doped thiazole, can behave as a superhalogen with high electron affinity value. In this study, DFT calculation found that the calculated electron affinity/vertical detachment energy of the synthesized dimer-NBS heterocyclic molecules is close to 2 eV. After ligand manipulation on the dimer, new superhalogens developed. Frontier molecular orbitals (FMOs) study helps to understand the variation of the electron affinity of the designed superhalogens. Topological analyses such as bond critical point (BCP), electron localization function (ELF), and AdNDP analysis support the bonding pattern of such heterocycle molecules. [ABSTRACT FROM AUTHOR]

Strength of acid can be determined by means of pKa value. Attempts have been made to find a relationship between pKa and activation energy barrier for a double proton transfer (DPT) reaction in inorganic acid dimers. Negative influence of pKa is observed on activation energy (Ea) which is contrary to the general convention of pKa. Four different levels of theories with two different basis sets have been used to calculate the activation energy barrier of the DPT reaction in inorganic acid dimers. A model based on first and second order polynomial has been created to find the relationship between activation energy for DPT reaction. © 2018 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The mechanism of ground and excited state double proton transfer reaction in formic acid dimer has been analyzed with the help of reaction force and the reaction electronic flux. The separation of reaction electronic flux in terms of electronic activity and reactivity, NBO, and dual descriptor lends additional support for the mechanism. Interestingly we found that the ground state double proton transfer mechanism is concerted synchronic, whereas the excited state double proton transfer is concerted asynchronic in nature. [ABSTRACT FROM AUTHOR]

We have computationally investigated the mechanism of Beckmann rearrangement in the framework of reaction electronic flux. The reaction has been studied in three different reaction conditions. The electronic transfer contribution of the reaction electronic flux was found to play a crucial role in this reaction. Natural bond order analysis and dual descriptor provide additional support for elucidating the mechanism of this reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Intermolecular P/B frustrated Lewis pairs can efficiently activate the water. • Intrinsic reaction coordinate (IRC) calculation prove that it is two steps reaction. • Natural bonding orbitals (NBO) analysis insights about the charge transfer. • The mechanism of water activation has been analyzed in the light of reaction electronic flux and its different separation. A new frustrated Lewis pair (FLP) is designed by using B(C 2 HBNSF 2) 3 and P(tBu) 3 as Lewis acid and base, respectively. The first principle calculation reveals the ability of this FLP to activate the H 2 O molecule in a two-step process. Bond stretch isomers of the intermediate are identified from intrinsic reaction coordinate analysis. The H 2 O activation mechanism is analyzed thoroughly by reaction electronic flux and its different components. Wiberg index lends additional support for the activation process. Natural bonding orbital (NBO) analysis gives more insights into the charge transfer processes of the reaction mechanism. [ABSTRACT FROM AUTHOR]

Most electrolytes currently used in Li-ion batteries contain halogens, which are toxic. In the search for halogen-free electrolytes, we studied the electronic structure of the current electrolytes using first-principles theory. The results showed that all current electrolytes are based on superhalogens, i.e., the vertical electron detachment energies of the moieties that make up the negative ions are larger than those of any halogen atom. Realizing that several superhalogens exist that do not contain a single halogen atom, we studied their potential as effective electrolytes by calculating not only the energy needed to remove a Li+ ion but also their affinity towards H2O. Several halogen-free electrolytes are identified among which Li(CB11H12) is shown to have the greatest potential. [ABSTRACT FROM AUTHOR]

Most electrolytes currently used in Li-ion batteries contain halogens, which are toxic. In the search for halogen-free electrolytes, we studied the electronic structure of the current electrolytes using first-principles theory. The results showed that all current electrolytes are based on superhalogens, i.e., the vertical electron detachment energies of the moieties that make up the negative ions are larger than those of any halogen atom. Realizing that several superhalogens exist that do not contain a single halogen atom, we studied their potential as effective electrolytes by calculating not only the energy needed to remove a Li+ ion but also their affinity towards H2O. Several halogen-free electrolytes are identified among which Li(CB11H12) is shown to have the greatest potential. [ABSTRACT FROM AUTHOR]

No organic molecules with electron affinities near or above those of halogens are known. We show for the first time that aromaticity rules can be used to design molecules with electron affinities far exceeding those of halogen atoms either by tailoring the ligands of cyclopentadienyl or by multiple benzoannulations of cyclopentadienyl in conjunction with the substitution of CH groups with isoelectronic N atoms. Results based on density functional theory revealed that the electron affinities of some of these organic molecules can reach as high as 5.59 eV, thus opening the door to new class of superhalogens that contain neither a metal nor a halogen atom. [ABSTRACT FROM AUTHOR]

Alkalimetal cations and halogen anions are well-known componentsof salts. New classes of molecules referred to as superalkalis andsuperhalogens exist whose properties resemble those of alkali andhalogen atoms, respectively. The former have ionization potentialssmaller than those of alkali atoms while the latter have electronaffinities larger than those of halogen atoms. Using gradient-correcteddensity functional theory we have examined the possibility that anew class of salts, referred to as supersalts, could be synthesizedwith superalkalis and superhalogens as building blocks. The possibilitythat hyperhalogens can be synthesized by using superalkalis insteadof alkali atoms as the core has also been examined. Examples of superalkalis(superhalogens) used in this study include Li3O, Cs2Cl, and Cs2NO3(BF4, BeF3, and NO3). While supersalts are found to be stable,the ability of superalkalis to form as the core of hyperhalogens islimited due to their large size. [ABSTRACT FROM AUTHOR]

Highlights: [•] In this study no encapsulation of methane molecule is found in 51262 and HF51262. [•] HF doping may be thermodynamically feasible for CH4@512 and CH4@51268. [•] HF doping causes no structural change in CH4@512 and CH4@435663. [ABSTRACT FROM AUTHOR]

The geometries of 8 dienes and 18 dienophiles are optimized at the B3LYP/6-311 + G (d) level. The ionization potential ( I), electron affinity ( A), electronegativity ( χ), hardness ( η), chemical potential ( μ), global electrophilicity ( ω), electron accepting power ( ω+) and electron donating power ( ω−) values are computed employing ΔSCF method. The net reactivity index (Δ [ABSTRACT FROM AUTHOR]

The mechanism of a simple SN2 reaction, viz;OH–+ CH3F = CH3OH + F–has been studied within the framework of reactionforce and reactionelectronic flux. We have computationally investigated three differenttypes of reaction mechanisms with two different types of transitionstates, leading to two different products. The electronic transfercontribution of the reaction electronic flux was found to play a crucialrole in this reaction. Natural bond order analysis and dual descriptorprovide additional support for elucidating the mechanism of this reaction. [ABSTRACT FROM AUTHOR]

Abstract: The multitopic pyrazine functionalized pro-ligand 2,6-bis(N-methylimidazolium)pyrazinedichloride, L-1; 2,6-bis(N-methylbenzimidazolium)pyrazinedichloride, L-2 and their respective Pd(II)–NHC complexes 1 and 2 have been synthesised and characterized by different spectroscopic methods and have been analyzed within a conceptual DFT framework. Single crystal X-ray structures of (L-1)PF6 and complex 1 have been determined. X-ray structure revels that 1 form a 12 member palladacycle. Both complex 1 and 2, catalyse the Suzuki coupling reaction very well and from experimental and theoretical findings it is concluded that complex 1 is slightly catalytically more active than 2. [Copyright &y& Elsevier]

An aromatic boron hydride B3H32- and its various Li/Li+ doped isomers have been studied at the B3LYP/6-311+G(d) and M06/6-311+G(d) levels of theory to assess their hydrogen storage potential. Different types of interaction energies, reaction enthalpies and reaction electrophilicities associated with the hydrogen adsorption process suggest that B3H32- itself and some of its Li-decorated analogues may turn out to be effective hydrogen storage material. Nucleus independent chemical shift and conceptual density functional theory based reactivity descriptors lend additional support. The temperature-pressure phase diagram identifies the temperature-pressure zone where the reaction Gibbs free energy for the hydrogen adsorption is negative making it a thermodynamically feasible process. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2012 [ABSTRACT FROM AUTHOR]

Hydrogen trapping ability of various metal-ethylene complexes has been studied at the B3LYP and MP2 levels of theory using the 6-311+G(d,p) basis set. Different global and local reactivity descriptors and the associated electronic structure principles provide important insights into the associated interactions. There exist two distinct classes of bonding patterns, viz., a Kubas type interaction between the metal and the H molecule behaving as a η-ligand and an electrostatic interaction between the metal and the atomic hydrogens. [ABSTRACT FROM AUTHOR]

Abstract: Theoretical investigation on planar and rings has been performed. The aromaticity of the rings has been analyzed through their nucleus independent chemical shift (NICS) values as well as the σ- and π-contribution of the Z-component of the induced magnetic field. Counter to a previously reported result [Chem. Phys. Lett. 432 (2006) 331], the ring is found to be a local minimum and aromatic with planar D6h symmetry. The ring exhibits conflicting aromaticity like . Both the and rings can be stabilized in presence of suitable counter cations and systems like N6Ca2 and N4Li2 can trap molecular hydrogen. [Copyright &y& Elsevier]

Structure, stability and reactivity of several metal clusters with or without hydrogen doping were studied using standard ab initio and density functional theory (DFT) calculations. Conceptual DFT-based reactivity descriptors and the associated electronic structure principles lend additional support towards understanding the stability of metal clusters upon hydrogen doping. Related aromaticity was analyzed through nucleus-independent chemical shift values. Site selectivity towards electrophilic and nucleophilic attacks were analyzed in terms of the corresponding local reactivity descriptors. Most of the metal clusters have the capacity to trap hydrogen molecules. [ABSTRACT FROM AUTHOR]

Standard ab initio and density functional calculations are carried out to determine the structure, stability, and reactivity of B12N12 clusters with hydrogen doping. To lend additional support, conceptual DFT-based reactivity descriptors and the associated electronic structure principles are also used. Related cage aromaticity of this B12N12 and nH2@B12N12 are analyzed through the nucleus independent chemical shift values. [ABSTRACT FROM AUTHOR]

The stability, reactivity and aromaticity of clusters of various noble gas atoms trapped in aromatic H3+and Li3+rings are studied at the B3LYP/6-311+G(d) and MP2/6-311+G(d) levels of theory. Electrophilicity, a gain in energy and nucleus-independent chemical shift values lend additional insights into the overall behavior of these clusters. [ABSTRACT FROM AUTHOR]

The stability, reactivity and aromaticity of clusters of various noble gas atoms trapped in aromatic H3+and Li3+rings are studied at the B3LYP/6-311+G(d) and MP2/6-311+G(d) levels of theory. Electrophilicity, a gain in energy and nucleus-independent chemical shift values lend additional insights into the overall behavior of these clusters. [ABSTRACT FROM AUTHOR]

The stability, reactivity and aromaticity of clusters of various noble gas atoms trapped in aromatic H3+and Li3+rings are studied at the B3LYP/6-311+G(d) and MP2/6-311+G(d) levels of theory. Electrophilicity, a gain in energy and nucleus-independent chemical shift values lend additional insights into the overall behavior of these clusters. [ABSTRACT FROM AUTHOR]

Various isomers of the trigonal dianion metal clusters, X32-, X = Be, Mg, Ca, and their mono- and disodium complexes are optimized at the B3LYP/6-311+G(d) level. Different conceptual density functional theory based reactivity descriptors as well as the induced magnetic field values are calculated to understand the stability and aromaticity of these systems. Possibility of bond stretch isomerism is explored. Genetic algorithm results lend additional insights into the structures of these isomers. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010 [ABSTRACT FROM AUTHOR]

Abstract: In the classical rhodium–diphosphine complexes-catalyzed asymmetric hydrogenation of enamide substrates, examination on the role of catalyst electronic polarizability in the origin of enantioselectivity reveals its linear free energy relationship with the product enantiomeric ratio that is much more pronounced than analogous correlation with steric effect in the same systems. From a conceptually novel scenario, this work suggests that the often-overlooked chiral catalyst local polarizability property may function as a controlling force in enantioselection thus has important implication in rational catalyst design. [Copyright &y& Elsevier]

Confinement causes drastic changes in bonding, reactivity and dynamics. Alkali metal atoms are excellent reducing agents due to their low ionization energies. On the other hand, high electron affinity values allow the halogen atoms to behave as powerful oxidizing agents. In this article, we have shown that those properties get changed in a confined environment created by two fullerenes differing in size. [ABSTRACT FROM AUTHOR]

• MD and ONIOM techniques were used to study the interactions of HCQ and the key-residues, KR of the RBD of SARS-CoV-2. • Heterogeneous binding of HCQ and the KRs of RBD was governed by the differential life-time of the hydrogen bonded water network anchoring HCQ and KR. • Intermolecular proton transfer facilitates most favorable Lys417:HCQ complexation. • Off-target bindings of HCQ need to be minimized to prevent the transmission in a more efficient manner. Interactions of hydroxychloroquin (HCQ) with the receptor binding domain (RBD) of SARS-CoV-2 were studied from atomistic simulation and ONIOM techniques. The key-residues of RBD responsible for the human transmission are recognized to be blocked in a heterogeneous manner with the favorable formation of key-residue:HCQ (1:1) complex. Such heterogeneity in binding was identified to be governed by the differential life-time of the hydrogen bonded water network anchoring HCQ and the key-residues. The intermolecular proton transfer facilitates the most favorable Lys417:HCQ complexation. The study demonstrates that off-target bindings of HCQ need to be minimized to efficiently prevent the transmission of SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Two hydrogen-bonded organic frameworks (HOFs) of formula Co(C 6 H 5 N 2 O) 3 (1) and [Ni(C 6 H 6 N 2 O) 3 ·H 2 O·ClO 4 (2) were synthesized by single pot reaction from the respective Syn-2-pyridinealdoxine (2-pdad) with separate reaction of Co(acac) 2 and Ni(ClO 4) 2 in MeOH. X-ray crystallography exposes that (1) and (2) crystallized in orthorhombic and monoclinic space group with Pbca and P 2 1 / c point group, respectively. In both complexes, the central metal atoms are surrounded by three molecules of 2-pdad through chelation with the nitrogen atom of the aldoxin moiety and form a hexa-coordinated octahedral complex. Complexes (1) and (2) have van der Waals interaction, intra and intermolecular hydrogen bonding and rare 3D pillar layer HOFs network. However, both complexes adsorbed Rhodamine B (RhB) compared to other dyes i.e methylene blue and methyl orange. The % of adsorption efficiency of RhB is high in presence of complex 1 , whereas complex (2) has a high efficiency for separation of dye molecule (RhB and MB). Moreover, the UV absorption spectrum of (1) and (2) was measured and maximum absorption peaks appeared at 224 nm and 280 nm, which suggest that the cobalt (III) complex bind to DNA via an intercalation binding mode whereas nickel (II) complex cannot bind to DNA. DFT Study observed that complex 1 (singlet) has the highest ionisation potential energy and softness and lowest stability and hardness compared to complex 2 (singlet or triplet). Image 1 • Synthesis of novel Co(C 6 H 5 N 2 O) 3 (1) and [Ni(C 6 H 6 N 2 O) 3 ·H 2 O·ClO 4 (2) complex. • Multidisciplinary application: Dye adsorption, Separation and DNA binding. • Both the complexes produce 3D pillar layer HOFs network. • Complex (2) has a high efficacy for separation of mixture of dye molecule (RhB and MB). • Complex 1 has binding ability to DNA whereas complex 2 has no DNA binding activity. • DFT Study: Complex 1 (singlet) has the highest ionisation potential energy, softness and lowest stability, hardness. [ABSTRACT FROM AUTHOR]

Based on first principle calculation, activation of CO2 has been analyzed thoroughly by using different conceptual density functional theory based descriptors like reaction force, reaction force constant, reaction electronic flux, dual descriptor, etc. via dihydrogenation reaction of B3N3, H2 and CO2. The total reaction is a two-step reaction where initially B3N3H2 is formed from the reaction between B3N3 and H2 and in the second step HCOOH is form due to the reaction of CO2 by B3N3H2. It has been found that the di-hydrogen reaction for the CO2 activation is endothermic in nature, which can be changed to exothermic reaction by applying proper external electric field. Movement of H2 plays an important role in the CO2 activation process. The reaction force constant, Wiberg bond index and its derivative reveal that the reaction is slightly asynchronous and concerted in nature. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bis-triazole-pyrene sugar derivative 1 was used to sense PA and Au(III) in an 80% aqueous ethanol system. • The dynamic excimer of 1 was effectively quenched after interaction with picric acid (PA) and Au(III) ions. • Receptor 1 demonstrated a 1:1 stoichiometric ratio with a low micromolar detection limit (0.05 µM for PA and 0.75 µM for Au3+). • The practical application of 1 for the detection of PA and Au(III) ions was executed. • The quenching mechanism and binding chemistry were established from DFT calculations. In this paper, we developed a bis-triazole-pyrene sugar derivative 1 to recognize PA and Au(III) in an 80 % aqueous ethanol system. The recognition ability of 1 toward PA and Au(III) was evaluated from spectroscopic studies and DFT calculations. The dynamic excimer emission of 1 was reduced efficiently with PA and Au(III) ions compared to other NACs, metal species and anions. The sugar backbone provides the actual stereochemistry for forming dynamic excimer in aqueous ethanol medium after excitation at 345 nm. The bis-pyrene system 1 generated intramolecular pyrene dynamic excimer emission in the aqueous system. After interacting with PA, the excimer quenching was attributed to the charge and energy shifting from electron-dense pyrene units to electron-lacking PA in the ground state. Receptor 1 demonstrated a 1:1 stoichiometric ratio for PA and Au(III) ion with low micromolar detection limits (0.05 µM for PA and 0.75 µM for Au3+). The quenching and interaction mechanisms were demonstrated from DFT calculations. The recognition property of 1 for PA was also executed in the solid-supported system. Finally, the practical usefulness of the proposed method was described by the PA and Au(III) recovery abilities in various environmental water systems. [ABSTRACT FROM AUTHOR]

Carbene and its analogous silylene and germylene ligated trinuclear gold complexes are well established due to their cationic stability, but the anionic stability of such complexes is still rare. Density functional theory calculations on recently synthesized [Au3{C4H4(SiMe3)4Si}3]− and [Au3{C4H4(SiMe3)4Ge}3]− prove that the Au3 core is electron rich and the calculated vertical detachment energy is close to that of halogens. Further proper ligand manipulation on these complexes makes them remarkably stable anions having electron binding energies higher than 5 eV and behaving like superhalogens. Magnetic response calculations based on the magnetically induced current densities and the induced magnetic field confirm the aromatic nature of these anionic Au3-complexes. A study of the gradient Laplacian of electron density and energy density at the bond critical point and electron localization function gives additional bonding information of these anionic complexes. [ABSTRACT FROM AUTHOR]

Imidazolium and its different N‐substituted derivatives are considered in this study to investigate their stability, reactivity, and acidity. Different aliphatic and aromatic ligands have been introduced in imidazolium to see their effect. It has been observed that the acidity of imidazolium systems increases with ligands having higher electron‐withdrawing nature. The studied systems are found to be weak acids, and weak bases can generate the corresponding carbene systems. The stability, reactivity, and aromaticity of all the systems are analyzed by using conceptual density functional theory (CDFT)‐based reactivity descriptors. Nucleus‐independent chemical shift (NICS) values lend additional support for the aromatic behavior of the studied molecules. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A triazole-linked glucofuranose as a colorimetric sensor for Cu2+ ion is reported. • The sensor could detect the Cu2+ ion in aqueous medium by naked eyes. • The sensor exhibited high selectivity for Cu2+ in the presence of other metal ions. • Sensing mechanism also established by DFT/TDDFT calculations. Abstract Simple and cost-effective triazole-linked glucofuranose derivatives 1 and 3 were designed, synthesized and characterized by NMR and HRMS. The high selectivity and sensitivity of sensor 1 towards Cu2+ were established by colorimetric, UV-vis, FTIR, HRMS, DFT and TDDFT experiments along with Uv-vis measurement of model compound 3. It exhibits the color change from yellow to colorless in presence of Cu2+ ion only over various cations and anions in a wide pH range which can be easily detected by naked-eye. The observed detection limit of 1 for Cu2+ ion was found to be 3.50 µM which is much lower than WHO's suggested value in drinking water (31 µM) and other reported values. [ABSTRACT FROM AUTHOR]

The back cover for the journal "Angewandte Chemie International Edition" is presented.

The assembly of atoms leads to the formation of clusters. These clusters have a tendency to gain their stability by forming either cations or anions. Among the anionic clusters, Zintl ions with multiple negative charges are a special type of inorganic complex generally formed from group 13, 14 and 15 elements in the periodic table. On the other hand, superhalogens are neutral molecules which have high electron affinity. Between the two different types of molecules, the former stabilized in the neutral state by forming a phase with alkali metal atoms, while the latter prefers the anionic state. Using first principle calculations, we show that it is also possible to design superhalogens having a Zintl core by functionalizing with suitable ligands like CF3, CN and NO2. The vertical detachment energies of these complexes indicate that they can be classified as superhalogens. The stability of these complexes is explained in terms of the jellium model. Density of states, partial density of states and natural localized molecular orbitals (NLMO) of these molecules lend additional information on the structure and bonding of these complexes. [ABSTRACT FROM AUTHOR]

A systematic study, based on density functional theory and different hybrid functionals for exchange-correlation potential, shows that the electron affinities of organo-zintl clusters [Ge 9 (R) n ] [R = CHO; n = 1, 3] are close to that of chlorine (3.6 eV) and iodine (3.0 eV). A detailed study of the molecular orbitals of these complexes, when compared to those of Al 13 − , Cl − and I − , confirm that they behave as superatoms, mimicking the chemistry of halogens. This study expands the scope of superatoms by including a new class of pseudo-halogens based on ligated organo-Zintl ions. [ABSTRACT FROM AUTHOR]

Inorganic superhalogens are commonly used as anionic counterparts in Li-ion batteries. In an endeavour to prepare better electrolytes, we have modelled the anionic part with different organic heterocyclic-based superhalogens. First principles calculations on those organic superhalogens reveal that the Li-binding energy is at par with that of the Li-salt of a common electrolyte. Out of five different halogen free organic heterocycles, Li[C3BN2(NO2)4] and Li[C2BNO(NO2)3] are found to be mostly suitable as electrolytes in Li-ion batteries. Molecular dynamics simulation studies on C2BNO(NO2)3−, C3BN2(NO2)4−, Li[C2BNO(NO2)3] and Li[C3BN2(NO2)4] also reveal that the structures are dynamically stable. [ABSTRACT FROM AUTHOR]

A correction to the article "Aromatic Superhalogens," that was published in a previous issue is presented.

A palladium-catalyzed protocol involving oxidative C-H sulfamidation of electron-deficient terminal alkenes is described for the stereoselective synthesis of Z-enesulfonamides. The possible intramolecular hydrogen bonding between the sulfamido proton (SO2N-H) and the carbonyl oxygen (C=O) of the ester group provides extra stability to the resulting alkyl-palladium complex as well as to the transition state. Notably, this reaction operates at room temperature under ligand-free conditions and does not require any inert atmosphere or dry solvent or expensive terminal oxidant. The present protocol enables the stereoselective synthesis of Z-enesulfonamides from the primary sulfonamides and of E-enesulfonamides from N-substituted sulfonamides. Furthermore, the selective deallylation of sulfonamides in the presence of an N-benzyl group was performed under the above reaction conditions. [ABSTRACT FROM AUTHOR]

Four new diferrocenyl hydrazone-enone compounds were obtained through a two-step reaction process involving 1,1′-diacetylferrocene, hydrazides, and ferrocenecarboxaldehyde. The structural characterization of two compounds, 6 and 7, through single-crystal X-ray diffraction showed the presence of a stable eclipsed conformation with the two ferrocenyl moieties oriented in trans geometries. The electrochemical and metal-ion sensing properties of the diferrocenyl-bifunctionalized compounds were explored to understand their potential in electronic communication and as receptor molecules. Compounds 1,1′-[(η5-C5H5)Fe(η5-C5H4)CH=CHC(O)(η5-C5H4)Fe{(η5-C5H4)C(CH3)=N-N(H)C(O)-R}] [R = C6H4OH ( 6), C6H4N- p ( 7)], showed selective interactions with Pb2+ cations and distinct binding interactions with bovine serum albumin (BSA) protein. The mode of the metal-receptor interaction was established through DFT studies. The redox properties of the diferrocenyl compounds with variable end groups revealed distinct electronic communication between the two electroactive groups. [ABSTRACT FROM AUTHOR]

The new bipolar ligand 4-{1-(9,9-diethyl-9 H-fluoren-2-yl)-1 H-imidazo[4,5- f][1,10]phenanthrolin-2-yl}- N, N-diphenylbenzenamine (Phen-Fl-TPA) and its β-diketonate EuIII complex have been designed, synthesized, characterized, and their photophysical and electrochemical properties have been investigated. The UV/Vis absorption and photoluminescence (PL) emission spectra of the Eu complex and Phen-Fl-TPA in solution as well as in the solid state and as thin films were recorded. The PL study indicated that the Eu complex emits narrow-band red emission with an appropriate International Commission on Illumination (CIE) color gamut. Moreover, it also confirmed the efficient energy transfer from the ligand to the Eu3+ ion. Time-dependent DFT (TD-DFT) calculations were performed for the ligand to determine the exact positions of the excited singlet and triplet energy levels. The EuIII complex shows a dominant pathway involving energy transfer between the ligand triplet level and the excited (5D0) level of the EuIII ion. In addition, the theoretically calculated UV/Vis spectrum of the ligand is similar to the experimental one. The Judd-Ofelt theory was applied to the emissive properties of the EuIII complex, and the lifetime was found to be 0.66 ms. The ground-state optimized ligand structure was a good match with the single-crystal structure. The photoluminescence quantum yield (PLQY) of Eu(TTA)3Phen-Fl-TPA (TTA = thenoyltrifluoroacetone) in solution was 34.1 %, and it possess a high thermal decomposition temperature (317 °C), as determined by differential scanning calorimetry/thermogravimetric analysis (DSC-TGA). Electrochemical analysis revealed highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels for the EuIII complex of 5.6 and 2.8 eV, respectively. [ABSTRACT FROM AUTHOR]

The authors respond to a commentary on their article which proposed an electrophilicity equalization principle. They noted that the proposal was made based on the principles of electronegativity equalization and hardness equalization. They clarified the relevance of density functional theory to their proposed principle.

Si- and Ge-doped imidazolium has been designed to analyze their stability, reactivity, and aromaticity. The first principle calculation on twelve different systems reveals their superacid nature. Gibbs's free energies of deprotonation are found to be greater than 300 kcal/mol. The stability and local reactivity have been analyzed in the light of several conceptual density functional theory-based reactivity descriptors like hardness, electrophilicity, philicity, etc. Nucleus-independent chemical shift (NICS) values support their aromatic nature. The calculation of dual descriptors and multiphilic descriptors lend additional support in terms of nucleophilic and electrophilic regions inside the molecules. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tri-nuclear Au 3 -core with tetrylene ligands (Silylene, Germylene) stable as cation. • Vertical electron affinity (VEA) of the designed complexes is lower than the alkali metal. • NICS calculation confirms the aromaticity of Au 3 -complexes. • EDA and Laplacian electron density at BCP give the bonding nature of designed superalkali systems. • The first order hyperpolarizability confirms the NLO properties of the Au 3 -complexes. Coinage metal [Cu, Ag, Au] complexes, with carbene analogous ligands, especially silylene, and germylene, have been getting attention in recent years for their potential applications, either in homogeneous catalysis or in photophysical properties. In this study, we have designed trinuclear gold complexes with different substituted silylene and germylene and observed that these trinuclear gold complexes are stable in cationic form and behave like a superalkali. Conceptual density functional theory (CDFT) based descriptors like electrophilicity give the idea about the reactivity of these superalkali complexes. Negative NICS values determine the aromatic nature of the trinuclear core of these complexes. Atom in molecules (AIM) study has been performed to gain a clear idea about the bonding nature of complexes. Energy decomposition analysis (EDA) suggests that electrostatic interaction stabilizes the complex. First-order hyperpolarizability calculation confirms their high nonlinear optical (NLO) properties. [ABSTRACT FROM AUTHOR]