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A series of mixed β-substituted porphyrins, 2,3,12,13-tetrakis(bromo/cyano/methyl)-5,7,8,10,15,17,18,20-octaphenylporphinatonickel(II)/copper(II), MOPPX4s (X = Br, CN and CH3; M = Ni(II) and Cu(II)) were examined in 24 different solvents with varying polarity. Among the porphyrins, MOPP(CN)4 show enhanced solvent dependent optical absorption spectral features relative to other porphyrins, MOPPX4 (X = Br and CH3) and MTPPs. Although, MOPP(CN)4 (M = Ni(II) and Cu(II)) have higher electron deficiency due to electron withdrawing β-cyano groups, comparable solvent dependent absorption spectral features and opposite trend in their shift of bands relative to the corresponding MTPPBr8 were observed. The large red-shift of the absorption bands of Cu(II) and Ni(II)-mixed substituted porphyrins in polar solvents or nitrogenous bases has been suggested to the destabilization of the HOMO (b2) relative to b1 (HOMO) level due to axial ligation of the polar solvents or nitrogenous bases with the core metal ions. The greater affinity of the core metal ions towards coordinating solvents or nitrogenous bases has been attributed to the electron deficient nature of the porphyrin π-system and follow the order: MOPP(CN)4 > MOPPBr4 > MOPP(CH3)4 due to inductive/resonance effect of β-substituents rather than the nonplanarity of the porphyrin ring.

Hexagonal YBO3 photocatalysts were successfully synthesized by hydrothermal method. The samples were characterized by XRD, SEM, TEM, XPS, UV–vis, photocatalytic performance, photocurrent and electrochemical impedance analysis. The results show that the pH value has a large effect on the formation of the microspheres. The excellent photocatalytic performance for RhB degradation depends on the exposed {1 0 1 ¯ 0} facets in which the fitting concentration of oxygen vacancy can prevent the recombination of the photogenerated carriers. Meantime, the {1 0 1 ¯ 0} faceted YBO3 microspheres enhance the absorption of irradiation light and present highest specific surface area which can also accelerate photocatalytic activity.

Solubility of SO2 in [N2224][Met] was measured at temperature from 313.2 to 333.2 K and pressure up to 1.8 bar. The [N2224][Met] absorbed SO2 at high speed and could be recycled for four times. The Reaction Equilibrium Thermodynamic Model (RETM) was used to correlate the experimental data, Henry’s constant (H), reaction equilibrium constant (K0), and thermodynamic properties ( Δ r H m 0 , Δ r G m 0 , Δ r S m 0 , Δ H phy a n d Δ H chem ) were derived. Considering the absorption capacity and low absorption enthalpy, as well as the fast absorption process, [N2224][Met] is thought to be a promising absorbent to ordinary solvent as a desulfurizer.

We have investigated chemical forms of molybdenum ion in nitric acid solution, using liquid-phase X-ray absorption fine structure, ultraviolet–visible absorption spectroscopy and first-principles calculations, from a viewpoint of disposal of high-level radioactive nuclear liquid wastes. The experimental and theoretical results indicated that Mo is a hexavalent ion and forms a hexa-coordination binuclear-structured complex in the 2M nitic acid solution. The predominant chemical species of Mo complexes in the 2M nitric acid solution (which is used for HLLW) are assigned to be [Mo2O5(H2O)6]^2+ and [Mo2O4(OH)(H2O)6]^3+. These species may play a crucial role of forming so-called yellow-phase in vitrified objects., ファイル公開：2021-05-16

In the reported work, we have approached the interaction of the amino acids onto the antimonene (Sb) monolayer by using density functional theory (DFT). Here, we have considered glycine (Gly), glutamic (Glu), histidine (HIE/His) and phenylalanine (Phe) biomolecules for interaction. The structural, electronic and optical properties have been investigated to understand the behavior. The adsorption of the biomolecules on Sb monolayer show the physisorption process. The adsorption energy of the phenylalanine (Phe) biomolecules is the most favorable. The optical absorption peaks of systems come in the near visible region. The studies conclude that Sb monolayer is useful for the bio-integrated electronics based devices.

Diluted solutions of Ce(NO3)3 and La(NO3)3 in ethylammonium nitrate (EAN) were investigated using molecular dynamics (MD) simulations and X-ray absorption near edge structure (XANES) spectroscopy. New La-O and Ce-O Lennard-Jones parameters were optimized to provide an accurate atomistic description of the nitrato complexes at low computational cost. XANES spectra analysis, along with radial and combined distance-angle distributions from MD simulations, indicate that the main metal species in solution is an icosahedral nitrato complex with a 12-fold cation-oxygen coordination and an equilibrium between monodentate and bidentate ligands.

This report describes how LiI mixes with thin propanol and butanol films at cryogenic temperatures using time-of-flight secondary ion mass spectrometry and reflection absorption infrared spectroscopy. The glass transition temperature, Tg, is assignable as the uptake onset of LiI additives in the thin film interior. The uptake rate of LiI in the deeply supercooled region is small for 1-propanol and 2-butanol, but concentrated solutions are formed on a LiI film at temperatures higher than 1.2–1.3 Tg. The supercooled 2-propanol and 1-butanol are short-lived; their crystallites form complexes at the interface with LiI because of premelting.

We aim to understand foreign gas effect on A-band of oxygen that is optical forbidden b 1 Σ g + ( v = 0 ) ← X 3 Σ g - ( v = 0 ) transition. To measure the absorption of weak A-band, a high pressure absorption spectroscopy system was constructed. We found absorbance around A-band of O2/M ( N2, CO2, SF6, Ne, Ar, Kr, Xe) gas mixture were larger than that of pure O2. This enhancement by foreign gases was discussed from a view point of heavy atom and polarizability effects under the light of the presented mechanism of the heavy atom effect. We performed quantitative analysis on the enhancement by noble gases, which are monoatomic molecules, as a foreign gas. The polarizability effect was examined by using SF6 as a foreign gas, which is a simple molecule with large polarizability.

In this study, the artificial chromatophore was constructed by reconstitution of light-harvesting complex 2 (LH2) and core-complex (LH1-RC) from Thermochromatium tepidum in egg phosphatidylcholine (PC) liposome. By calcium ion dependent absorption changes, the orientations of protein complexes in liposomes solely were assigned. Ultrafast EET dynamics were studied by fs time-resolved absorption spectroscopy on both the artificial and natural chromatophores at their RC ‘open’ and ‘close’ states, respectively. The results indicated that these two membrane systems have similar EET dynamic profiles, and the orientations of LH2 and LH1-RC complexes in artificial chromatophores were opposite to those in natural chromatophores.

Mg is promising as a new light-weight and low-cost hydrogen-storage material. We construct a numerical model to represent the hydrogen dynamics on Mg, comprising dissociative adsorption, desorption, bulk diffusion, and chemical reaction. Our calculation shows a good agreement with experimental data for hydrogen absorption and desorption on Mg. Our model clarifies the evolution of the rate-determining processes as absorption and desorption proceed. Furthermore, we investigate the optimal condition and materials design for efficient hydrogen storage in Mg. By properly understanding the rate-determining processes using our model, one can determine the design principle for high-performance hydrogen-storage systems.

Samples in the 5Fe2O3·10SiO2·xY2O3·(85-x)ZrO2 composition where x = 5, 10 and 15 mol% Y2O3 were synthesized and investigated by XRD, SEM, density measurements, FTIR, UV–Vis, EPR and PL spectroscopies. X-ray diffraction patterns confirm the presence of the tetragonal and cubic ZrO2 crystalline phases in all samples. The IR data show the overlaps of absorption bands assigned to Zr O Zr and Si O linkages in samples. UV–Vis and PL data indicate higher concentrations of intrinsic defects by doping with Y2O3 concentrations. The EPR spectra are characterized by two resonance lines situated at about g ∼ 4.3 and g ∼ 2 for lower Y2O3 contents.

Application of carbon nanotube (CNT) film as a gas sensor is highly desired. Transient behavior of molecular adsorption provides adsorption and desorption constants; however, to date, few researchers have investigated it. Here, we focused on the transient behavior of electric conductance of the CNT film during adsorption. Adsorption of polar molecules showed predicable behavior, but non-polar molecules showed a sudden change of electric conductance that indicated excess adsorption. We analyzed the process based on Langmuir adsorption, and adsorption and desorption constants, which are considered to be physical properties; however, these parameters did not show good agreement for the same film.

Open edge BN boron-nitride has a stable graphene-like structure, which could be doped by a range of impurities, so the band gap could be tuned. The optical, electrical, physicochemical properties, NBO and electron density of open edge BN that is doped by Yttrium was evaluated using DFT method as a sensor for He gas. Here, was applied HSE1PBE method exchange correlation and LANL2DZ. The density of states and natural bond orbital analysis calculated have depicted that the band gap of BN-Y flake after sensing He gas and it has shown change from 1.66 → 2.42 eV. The UV–Vis absorption in λmax area showed a significant red-shift that it is an appropriate parameter to recognize He molecule.

The detecting mechanism in a dual-mode fluorescent probe PYNA sensing to tryptamine and fluoride ions has been explored by theoretical methods. The excited state intra-molecular proton transfer (ESIPT) process was investigated through analyzing excited hydrogen bonding changes, potential energy curves, frontier molecular orbitals and the charge density redistribution. Meanwhile, the excited state behaviors of PYNA-F, which is the product of PYNA reacting with fluoride ions, are analyzed to demonstrate the fluorescence detecting mechanism of PYNA for fluoride ions. The experimental new absorption peak of 480 nm has been assigned to the absorption of the anion form of PYNA.

A colorimetric sensor for detection of Ni2+ with high sensitivity and selectivity has been developed by functionalizing gold nanoparticles (AuNPs) with phytate (PA) in aqueous solution. The as-prepared PA-AuNPs exhibit the excellent selectivity for colorimetric detection of Ni2+ over 13 metal ions in 15 min. In the presence of Ni2+, the color of PA-AuNPs changes from red to blue, and the plasmon absorption exhibits a redshift. The detection limit of PA-AuNPs is found to be 5 μM and 0.216 μM for naked eyes and UV–vis spectroscopy on basis of signal-to-ratio of 3:1 respectively.

The electronic structure and optical properties of O adsorbed ReS2 monolayer under different biaxial strains were studied through Density Functional Theory. Strain reduces the band gap of O adsorbed ReS2 monolayer, the band gap varies greatly reaching 1.509 eV under strain of −10%. Both the absorption intensity and reflectivity change significantly under strains. The adsorption coefficient reaches maximum value of 27.08 × 104 cm−1 under strain of −10% within the ultraviolet range. Our research shows that strain can effectively modulate the optoelectronic properties of O adsorbed ReS2 monolayer, which provides helpful guidance for the application of ReS2 in nanoscale optoelectronic devices.

Photoelectron detachment yield (PDY) spectroscopy is an effective tool for elucidating gas phase protein structures compared with other spectroscopies in aqueous solutions. In general, investigations of low-charged ions are necessary to elucidate the intrinsic properties of protein because excess charge perturbs the electronic state of the protein. In this study, we measured PDY spectrum of the most low-charged cytochrome c (cyt c) anion, [cyt c]- by IR-laser ablation of a droplet beam. This result shows a spectral blueshift from the absorption peak of aqueous cyt c and the PDY peak of the [cyt c]6- ion reported in the previous study.

Hydration structures of barium ion (Ba2+) were studied by ab initio molecular dynamics using the strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation (GGA) exchange-correlation (XC) functional and extended X-ray absorption fine structure spectroscopy, which showed consistent results for the static properties. The result obtained with SCAN was compared with these with the Perdew–Burke–Ernzerhof (PBE) and Becke–Lee–Yang–Parr (BLYP) GGA XC functionals and the functionals with the Grimme’s dispersion correction (PBE-D3 and BLYP-D3). The comparison revealed the importance of the dispersion interaction for the static and dynamic properties of the Ba2+ hydration structures.

The aqueous reaction of piperazine and copper chloride dihydrate yielded piperazine-1,4-diium tetrachloridocuprate(II) hydrate (PCu) cocrystal. Acid hydrolysis during pH optimization produced cationic piperazine-1,4-diium, which was neutralized by anionic tetrachloridocuprate(II) to form a stable ionic cocrystal. The PCu single crystal belongs to the space group C 2 / c of the monoclinic crystal system. High linear absorption with indirect bandgap and least possible crystal defects are coherently supported to the two-photon absorption assisted optical limiting phenomena in PCu cocrystal. The third order nonlinear refractive index ( n 2 ), absorption coefficient ( β ) and susceptibility ( χ ( 3 ) ) of title material are found to be (0.635 ± 0.0058) × 10 - 8 cm2W−1, (0.232 ± 0.001) × 10 - 4 cmW−1, (2.63 ± 0.01) × 10 - 6 esu respectively under continuous-wave laser (100 mW, 532 nm) excitation shows its suitability for nonlinear optical device applications. The variation in β measured at different nanosecond pulsed laser intensities confirmed the presence of sequential two-photon absorption. The noncovalent intermolecular charge transfer responsible for sequential two-photon absorption in PCu cocrystal is theoretically proved possible using DFT-UB3LYP/LANL2DZ+6-311G** level of quantum mechanical calculation. The onset optical limiting threshold values were measured to be (0.394 ± 0.02) × 10 03 Wcm−2 and (1.62 ± 0.02) × 10 12 Wm−2 for 100 mW continuous wave laser and 100 μ J nanosecond pulsed green laser (532 nm) irradiance respectively. Hence the PCu cocrystal can be a promising candidate for optofunctional applications.

Nickel oxide (NiO) particles were synthesized by varying temperature through solid-state combustion method. The effects of annealing temperatures such as 650, 750, 850, 950, and 1050 °C, on the crystallite size, absorption properties, and photodegradation of methylene blue (MB) were studied. Progressive enhancement of crystallinity of the samples was clearly observed in FE-SEM images. The photocatalytic degradation of MB with different crystallite sizes was studied, showing that degradation increases with increasing the sample's crystallinity. The percentage of degradation of MB dye is found to be 96% in three hours. Furthermore, the density functional theory (DFT) studies have been performed for NiO to understand the linear optical and chemical properties. The DFT results are found to have a good correlation with the experimental findings.

Interfacial charge-transfer transitions (ICTTs) between organic compounds and inorganic semiconductors have recently attracted increasing interest for their potential applications in solar energy conversions and biosensing due to the key features of visible-light absorption with colourless organic molecules and direct photoinduced charge separation. Recently, we first reported ICTT between ZnO nanoparticles and aromatic thiols such as benzene thiol (BT). Here, we computationally examine ICTT between ZnO and BT with density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations. Our research provides the definitive assignment of ICTT in the ZnO-BT surface coordination complex and clarifies the mechanism of the ICTT.

Diamino protic ionic liquids (DPILs) possess a wide application prospect in the field of gas separation and absorption. In this work, two kinds of DPILs, dimethylethylenediamine 4-fluorophenolate ([DMEDAH][4-F-PhO]) and dimethylethylenediamine acetate ([DMEDAH][OAc]) were selected to investigate the microstructure properties and interaction mechanism of [DMEDAH]+ cations with different [4-F-PhO]-/[OAc]- anions by density functional theory (DFT) method. The stable configurations were determined at B3LYP/6-311+G (d, p) level, and the effects of solvent water molecules on the structure were investigated. Based on this, the different interaction mechanisms and the structural/charges parameters were revealed.

Diapers are reusable waste. This research presents physicochemical properties of sodium polyacrylate in new (ND) and used (UD) diapers, via wavelength-dispersive X-ray fluorescence (WDXRF), Fourier transform infrared (FTIR), X-ray diffraction (XRD), pH, turbidity and colour. Additional constituents detected in ND, while others were slightly higher in UD. Slight decrease (2000–2500 cm−1, UD) and bulk peaks (3287–3333 cm−1, UD) were observed and functional group at 2897 cm−1 (ND) disappeared showing their role as absorption sites. The pH (6.83–8.50), turbidity (16.3–36.6 NTU) and colour (153–432 Pt.Co) values were obtained. Thus, this provides a baseline reference for diapers application in concrete technology.

Chemically tuned inorganic–organic hybrid halide perovskites based on iodine and bromine halide anions have been studied using first-principles calculations. Firstly, our results show that the volume of CH 3 NH 3 Pb ( I 1 - x Br x ) 3 decreases linearly with the concentration of Br ions, and the band gap can be tuned from 1.9 eV to 2.3 eV by substituting I with Br, resulting in the shift of absorption onset from 650 nm (1.9 eV) to 540 nm (2.3 eV). Secondly, our calculations show that the color of crystal can be tuned from wine to yellow by substituting I with Br.

We report a novel synthesis of stable doped solid carbon monoxide (p-CO) via hard X-ray irradiation of strontium oxalate at ambient conditions and high pressure. We also show via mid- and far- infrared (IR) techniques that CO2 produced via X-ray photochemistry remained trapped within the recovered sample for many months in contrast to pure p-CO which decomposes in days. Our results demonstrate that p-CO doped with carbonates (as verified with IR and Extended X-ray Absorption Fine Structure spectroscopies) is relatively stable, enabling longer term and practical use of this novel material for CO2 storage or as a novel electrical/optical material.

Chemical denaturation of protein represents a secondary/tertiary structural change, which has been measured by absorption and CD spectra in the liquid phase. In this study, we used gas-phase photoelectron detachment yield (PDY) spectra for elucidating isolated structures of bovine serum albumin (BSA) ions and their conjugated ions with cetyltrimethylammonium bromide (CTAB), whose conjugation causes a significant chemical denaturation in the protein structure. The obtained PDY spectrum of BSA ions shows a broad peak near 208 nm, which significantly disappears in that of CTAB-denatured BSA. This result indicates the CTAB-denatured BSA has a stable unfolding structure in the isolated water cluster.

This communication reports the effect of building matrices and nano clay platelets on the aggregation pattern of a water soluble cationic fluorescent dye Crystal Violet (CV) in Langmuir-Blodgett (LB) Films. When stearic acid (SA) was used as a building matrix, pressure induced changes in metachromasy was observed in the SA-CV complex LB films with a characteristic J-band formed at the longer wavelength side. On the other hand, clay incorporated hybrid LB films showed high degree of control over H-dimeric band. Isotherm characteristics, Brewster Angle Microscopic (BAM) images, UV–vis absorption and fluorescence characteristic studies were employed to investigate this result.

This work reports rate coefficients of the thermal unimolecular decomposition reaction of ethyl propionate (EP) behind reflected shock waves over the temperature range of 976–1300 K and pressures of 825–1875 Torr. The reaction progress was monitored by detecting C 2 H 4 near 10.532 μm using CO 2 gas laser absorption. In addition, G3//MP2/aug-cc-pVDZ and master equation calculations were performed to assess the pressure- and temperature-dependence of the reaction. Our calculations revealed that C 2 H 4 elimination occurs via a six-centered retro-ene transition state. Our measured rate data are close to the high-pressure limit and showed no discernable temperature fall off.

Usually the stretching vibration of the A-H group in hydrogen-bonded complexes gives an intense, broad absorption in the IR spectrum. However in a few complexes it has proved difficult to detect this absorption in low temperature matrices. In this work the Ratajczak-Yaremko vibrational model of the hydrogen bond has been applied to simulate the IR spectrum obtained for one such complex: the pentachlorophenol-trimethylamine, PCP-TMA, hydrogen bonded complex isolated in an argon matrix. Quantum chemical calculations have also been carried out to gain further insight into this complex.

Interfacial charge-transfer (ICT) transitions between wide-band-gap semiconductors such as titanium dioxide (TiO 2 ) and π-conjugated molecules enable the absorption of visible light with colorless organic compounds and also direct photoinduced electron transfers across the interfaces. ICT transitions have been reported to be induced by a double Ti O C linkage of enediol compounds with two hydroxy groups to TiO 2 . In this Letter, we demonstrate that a single Ti O C linkage of phenol with one hydroxy group can induce ICT transitions in the visible region. Our result widely opens up the range of organic compounds available for ICT transitions from diol compounds to mono-hydroxy compounds.

Interfacial charge-transfer (ICT) transitions between inorganic semiconductors and π-conjugated molecules allow direct charge separation without loss of energy. This feature is potentially useful for efficient photovoltaic conversions. Charge-transferred complexes of TiO 2 nanoparticles with 7,7,8,8-tetracyanoquinodimethane (TCNQ) and its analogues (TCNX) show strong ICT absorption in the visible region. The ICT band was reported to be significantly red-shifted with extension of the π-conjugated system of TCNX. In order to clarify the mechanism of the red-shift, in this work, we systematically study electronic structures of the TiO 2 –TCNX surface complexes (TCNX; TCNE, TCNQ, 2,6-TCNAQ) by ionization potential measurements and density functional theory (DFT) calculations.

A RTIL (room temperature ionic liquid) containing iodine/iodide (RTIL-I) was studied to determine its coated copper extraction efficiency on the surface of scrap Cu/indium tin oxide (ITO) thin films. According to the X-ray absorption near edge structural spectra and transmission electron microscopy observations, about 95% of Cu with the size of 80 nm was stripped from scrap Cu/ITO thin film into the RTIL-I and then formed 90 nm of α-CuI and CuI2− within 30 min at 298 K. The 31P NMR (nuclear magnetic resonance) spectra suggests [PF6]− of the RTIL-I may enhance the extraction of nanoparticles into the RTIL-I.

By using G09 program package, the absorption and fluorescence/phosphorescence spectra of dipterex were explored, and its spectroscopic characters were altered by methacrylic acid (MAA) as the imprinted molecule. The TD-DFT results revealed that: (1) All absorption and emission excitations of dipterex are assigned to the nσ ∗ transition; (2) without MAA as imprinted molecule, one of the dipterex C Cl bonds is extended significantly and dipterex is almost destroyed in transition states; (3) dipterex is connected to methacrylic acid via two hydrogen bonds; (4) for the dipterex–MAA complex, the electronic excitation (ππ ∗ excitation) in absorption spectra is dominated by the configuration HOMO → LUMO.

First principles calculation of the oxygen K-edge absorption near-edge structure of liquid acetic acid was performed to investigate the relationship between the spectrum and the molecular dynamics in a liquid. The single and double bonded oxygens gave strong peaks at different energies. A liquid model constructed using a molecular dynamics simulation reproduced the experimental spectrum. We revealed that the effect of the dynamic behavior of molecules in a liquid clearly appears in the particular peak from a single-bond oxygen. The relationship between the bonding nature and the dynamic information of a molecule in a spectrum was determined and presented.

We study spin-forbidden transitions of Os polypyridyl sensitizers by two-component relativistic time-dependent density functional theory with the spin–orbit interaction based on Tamm–Dancoff approximation. The absorption spectra, including spin-forbidden-transition peaks, for the Os complexes are reasonably reproduced in comparison with the experimental ones. The extension of the conjugated lengths in the Os complexes is investigated and found to be effective to enhance photo absorption for spin-allowed transitions as well as spin-forbidden ones. This study provides fruitful information for a design of new dyes in terms of conjugation lengths.

This work describes the second and third orders of nonlinear optics properties of unsubstituted chalcone (C15H12O) and mono-substituted chalcone (C16H14O2) in solution, using hyper-Rayleigh scattering and Z-Scan techniques to determine the first molecular hyperpolarizability (β) and the two-photon absorption (2PA) cross section respectively. β Values of 25.4 × 10−30 esu and 31.6 × 10−30 esu, for unsubstituted and mono-substituted chalcone, respectively, dissolved in methanol have been obtained. The highest values of 2PA cross-sections obtained were 9 GM and 14 GM for unsubstituted and mono-substituted chalcone, respectively. The experimental 2PA cross sections obtained for each chalcone are in good agreement with theoretical results.

The effect of the partial charge distributions on the adsorption of CO2 molecules in ZIF-8 framework has been obtained using GEMC simulations. The charge models are derived from the ab initio electrostatic potential surfaces of framework fragments. The signs of the atomic charges obtained with the MK model are more consistent with respect to the basis set than those obtained from the other models. The charges on the H1 and H2 atoms are found to have a notable effect on the amount of absorbed CO2, in agreement with a previous mention that these hydrogen sites are the favored absorption sites.

Six C34 isomers were theoretically identified by X-ray photoelectron spectra (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectra. The XPS and NEXAFS spectra of K-edge for all non-equivalent carbon atoms were simulated by density functional theory method combined with the full core-hole potentials. The XPS spectra mainly showed dependence on the isomers with different symmetries. Strong isomer identification of the NEXAFS spectra for C34 was found and discussed in detail. Furthermore, the spectra components of carbon atoms with different local environment were explored. The NEXAFS spectra dependence on the local structure of fullerene was discussed as well.

We studied the structural stability, electronic and optical properties of CH3-xFxNH3GeI3 (x = 0, 1, 2, 3) halide perovskites for the first time. The results reveal that CH3NH3GeI3 is the most stable structure among the CH3-xFxNH3GeI3 compounds. The addition of fluorine in CH3NH3 leads to the reduced stability of CH3NH3GeI3. When the H atoms of CH3NH3 one by one are replaced by fluorine atom, the CH3-xFxNH3GeI3 compounds have larger band gaps and show decreased optical absorption coefficients. These results suggest that the effect of fluorine on the organic cation has a significant influence on the material properties of CH3NH3GeI3.

By introducing Cu and Fe ions into the Polyvinylpyrrolidone (PVP) polymer, its photonic band gap is reduced from 5.0 eV to 3.4 and 2.7 eV respectively, whereby the absorption and optical sensitivity in visible are greatly enhanced. After laser irradiation, the formed composite can be cross-linked and solidified. High quality photonic crystals are produced in Fe3+-PVP composite film. Our research will help us understanding the interaction mechanism between metallic ions and polymers under laser irradiation. The composite material system will find wide applications in polymer-based optical devices.

The carbon 1s near edge X-ray absorption fine structure (NEXAFS) spectra of liquid phase n-alkanes have been measured for the first time. Clear trends are observed in the liquid phase spectra as a function of chain length. Specifically, the ‘C-H band’ in the NEXAFS spectra shifts to lower energy as the chain length increases. Characteristic differences between the gas, liquid and solid phase spectra are observed. Differences in the liquid phase n-alkane NEXAFS spectra are examined through molecular dynamics simulations coupled with density functional theory simulations of the NEXAFS spectra.

Metal ion or non-metal ion doping is a simple and effective method to improve the photocatalytic efficiency. The previous research showed that metal ion and non-metal ion could enhance the photocatalytic efficiency of BiOCl through different mechanisms. Since aluminum is an amphoteric metal elemental, Al3+ doping may exhibit special properties. To study the effect of Al3+ doping on the structure of BiOCl and its photocatalytic performance, Al-doped BiOCl microspheres which were assembled by nanosheets with exposed (0 0 1) crystal plane were prepared by solvothermal method. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS). The degradation results displayed that Al-10.0-BiOCl with a doping amount of 10 atom% (Al: Bi = 1:10) was the optimized sample and it could degrade 91.1% of tetracycline hydrochloride (TC, 100 mg/L) within 60 min under simulated sunlight irradiation. It was confirmed ·O2– was the main active substance during the catalytic degradation of TC and the high photocatalytic performance may be mainly attributed to the large specific surface area, wide range of sunlight absorption and high charge separation efficiency. To study the effect of the Al3+ doping on the structure of BiOCl and its photocatalytic performance, novel Al-doped BiOCl microspheres assembled by nanosheets with exposed (0 0 1) crystal plane were prepared by a solvothermal method. The samples were characterized and the photocatalytic activity was evaluated by degradating tetracycline hydrochloride under simulated sunlight irradiation. The results showed that Al-BiOCl with a doping content of 10 at% (Al: Bi = 1:10) exhibited optimal photocatalytic performance, and the high photocatalytic performance of Al-BiOCl may be mainly attributed to the large specific surface area, wide range of sunlight absorption and high charge separation efficiency.

A model of polypropylene membrane modified with acrylic acid has been proposed to understand the experimental removal efficiency of Cd2+, Cu2+ and Pb2+. To provide a description for bimetallic complexes, Ab Initio MD and Quantum Topological Analysis were carried out. Δ K S , q and Δ G values have been calculated and it has been observed that Δ K S (12acr) drives the metal absorption, where the stabilization is higher for copper–containing complexes. Δ K S (12acr) has presented the same tendency as the experimental removal efficiency. Thus, the model proposed can explain the experimental data and it can clarify the metal contributions to the absorption process.

A lead(II) organic-inorganic hybrid perovskite material [(TMA)2(MA)2Pb3I10] (1) has been synthesized by reactions of 2-thienylmethylamine (TMA) and methylamine (MA) with PbI2 in HI/H3PO2 aqueous solution. The crystallographic diffraction indicated the inorganic moiety in 1 is a trilayered perovskite structure constructed with [PbI6] octahedra, and the two organic amines are located between the inorganic layers, or embedded in the octahedral cavity of inorganic layers. The solid UV–vis absorption peak of compound 1 is located at 600 nm, and the bandgap calculated by DFT is 1.60 eV, both indicating it is a semiconductor and has potential application in organic-inorganic hybrid solar cell.

A novel compound (B18H20(NC9H7)2) was synthesized by connecting isoquinoline moieties to the anti-B18H22. The fluorescence emission performance in tetrahydrofuran/water mixtures showed that the compound had obvious aggregation-induced emission characteristic. Upon addition of water in tetrahydrofuran (90:10, v/v) solution, the quantum yield is increased by 0.04–1.41%. The photophysics properties of B18H20(NC9H7)2/polystyrene and B18H20(NC9H7)2/anti-B18H22/polystyrene film were also studied, and the testing results show that these two films have a wide range of absorption in the visible region. Our work broadens the structure types of anti-B18H22 derivatives and provides a new way to develop new anti-B18H22 fluorescent materials containing isoquinoline units.

The adsorption behaviors of oxygen atoms and water molecules on the cinnabar unit were studied using the density-functional theory (DFT) calculations. The pure cinnabar (CB) is a D3h-symmetrical ring structure, and the two oxygen atoms are energetically favorable to be bonded with the S atoms of the CB unit. The adsorption of water molecules keeps the geometric skeleton of complexes, and makes these hydrated structures stable. Moreover, the electronic and spectroscopic properties of the hydrated complexes are tailored. The UV–vis absorption and infrared vibrational spectra of these complexes are assigned.

The UV-induced photocoloration of cubic zirconia (c-ZrO2) stabilized by Y2O3, Yb2O3 and Er2O3 and treated as a wide bandgap metal oxide (MO2) heavily doped with M3+ ions has been examined by diffuse reflectance spectroscopy. Using the narrow f-f absorption bands of optically labeled Yb3+ and Er3+ as the M3+ dopants, the interaction of these dopant ions with photocarriers is demonstrated spectroscopically against a non-resolved broadband background. The latter occurs as a result of an offset of specific f-f absorption bands following conversion of M3+ ions into optically silent M2+ ions by the trapping of photoelectrons or by a change of the local symmetry of the M3+ surroundings caused by the UV-induced formation of color centers.

Theoretical investigation on a series of Pt(Ⅱ) complexes to evaluate the influence of diphenylamine group on the optical properties and their potential applications in PhOLEDs. The effect of different substituent positions (1a-1c) on the electronic structures and optical properties were fully explored by compared with the experimental synthesized complex 1. The functionalized diphenylamine moiety can tune the geometrical structures, frontier molecular orbitals, absorption and emission spectra, radative rate (kr), possbile nonradative process T1(3MLCT/π → π*) → TS(d-d)→3MC(d-d) → MECP(d-d), charge injection and transfer properties. The findings could help to understand the influnece of dipenylamine group and design high efficient red guest emitters in PhOLEDs.

In some of the technological applications (electromechanical oscillators and mechanical actuators for artificial muscles, for instance), carbon nanotubes (CNT) are subjected to large deformations. Although this frequently happens in the air, there are only a few studies about the interaction of deformed CNT with the atmosphere and the dynamics of these processes. We have investigated, through fully atomistic reactive molecular dynamics simulations, the process of hydrogenation of highly twisted CNT. Our results show that the effective hydrogenation ratio is directly related to the twist angle values. This could be used to control the rates of gas absorption in CNT.

Aromatic amines were reported to show visible light absorption by the adsorption on TiO2 nanoparticles, enabling visible light responsive photocatalytic reactions. However, the origin of the visible light absorption and the chemisorption structure have not been elucidated in detail yet. Here, we demonstrate experimentally and computationally that the visible light absorption in the TiO2-indole surface complex is attributed to interfacial charge-transfer transitions (ICTT) from the adsorbed indole to TiO2, supporting the chemisorption structure of indole via a Ti-N bond formed by the dehydration reaction with a surface hydroxy group. The ICTT originates from π(indole)-dπ(Ti) electronic couplings through the Ti-N bond.