Hong-Xing Zhang

Jilin University, Yung-chi, Jilin Sheng, China

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Publications (251)694.29 Total impact

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    ABSTRACT: A series of fluorescent probes were investigated to explore the mechanism of the detection for CN−, and all of the probes have an indolium group. The interaction between the functional group and the cyanide ion was simulated to examine the selectivity of these probes. The influences of some other anions were also tested in the cyanide detecting process. The different binding abilities between CN− and F− in aqueous solution were distinguished using the potential energy calculations in consideration of hydrogen bonding interactions. The large change of the emitting wavelengths of the fluorescent probes before and after the addition of CN− was explained through the analysis of the molecular orbital properties. The results indicate the large structural change results in a significant emission shift when each probe captures a cyanide ion. According to this conclusion, new fluorescent probes were designed.
    No preview · Article · Mar 2016 · Organic Electronics
  • Xin Wang · Fu-Quan Bai · Ying-Tao Liu · Jian Wang · Hong-Xing Zhang
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    ABSTRACT: Exploring the relationship between the geometrical structures and spectral properties has great significance to design some desirable materials. For important pyrrole contained macromolecules, there is a new complex of Zn tetrapyrrin with opened chain ligand derived from breaking one methine bridged of Zn porphyrin. The frontier molecular orbitals, absorption and emission properties of such Zn tetrapyrrin complexes are investigated by density functional theory (DFT) and its time-dependent density functional theory (TD-DFT) methods. Compared to Zn porphyrin, the HOMOs and LUMOs are no longer degenerate, the lowest lying absorption and emission of Zn tetrapyrrin start to increase in intensity with the shifting of charge transfer transition band to near-infrared region. We hope these theoretical studies will assist the design of novel molecular materials.
    No preview · Article · Mar 2016 · Synthetic Metals
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    Mo Xie · Fu-Quan Bai · Jian Wang · Chui-Peng Kong · Jie Chen · Hong-Xing Zhang
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    ABSTRACT: We report a theoretical study to ascertain dye regeneration in dye sensitized solar cells (DSSCs) with the TiO2-dye-electrolyte model. Oxidized 3-(5-(4-(diphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid (L2) dye, three electrolyte main components (I-, I2, I3-) and (TiO2)9 cluster has been selected in this model. The calculated results show that the combination capability of electrolyte to L2+@TiO2 is according to the order of I- > I3- > I2. Furthermore, oxidized dye together with electrolyte can get good performance of absorption in visible light region. Specifically, I- may accelerate the electronic transition and injection by participating in the positive charge transfer. I2 may lead to the opposite transition and I3- ions seem to be a mixed result of both effects. In this study, the charge transfer pathway during dye regeneration process has been found. It can be predicted that the charge transfer of dye regeneration may contribute to the absorption in UV-vis region of DSSC.
    Full-text · Article · Jan 2016 · Computational Materials Science
  • Ting-Ting Feng · Fu-Quan Bai · Li-Ming Xie · Yongan Tang · Hong-Xing Zhang
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    ABSTRACT: A density functional theory and time-dependent density functional theory investigation were performed on the geometrical structures, basic photophysical properties, phosphorescence quantum efficiency (ФPL), and reorganization energy (λ) calculations of a new potential class of tetradentate Pt(II) complexes Pt[ppz-O-Popy] (1) (where ppz = phenyl-pyrazole; Popy = phenoxyl-pyridine), Pt[pmi-O-Popy] (2) (where pmi = phenyl-methylimidazole), Pt[pmi-O-Cbpy] (3) (where Cbpy = carbazolyl-pyridine) and Pt[ppz-O-Cbpy] (4), which show highly efficient (ФPL>80%) and deep-blue emission. Nonradiative decay processes were investigated in order to obtain a more reliable nonradiative decay rate comparison. The calculated results confirm that tetradentate Pt(II) complexes are conducive to maintaining the rigidity of the molecules. The extended conjugation complexes with carbazole groups in 3 and 4 can not only improve the structural rigidity but also enhance the capability and balance of charge transfer. Thereupon, the following two designed derivatives Pt[pmi-O-Cbmi] (5) and Pt[pmi-O-Cbbm] (6) which substitute pyridine with imidazole and benzimidazole based on complexes 3 and 4 are also considered for promising materials exploitation and theoretical understanding. The charge transfer balance performance and the radiative decay rate constant (kr) of 5 and 6 are greatly improved compared with 1-4, and the better structural rigidity will weaken nonradiative decay pathways, which may result in higher phosphorescence quantum efficiency. Therefore, complexes 5 and 6 through judicious molecular design will be promising candidates as highly efficient blue-emitting phosphorescent materials for OLEDs applications.
    No preview · Article · Jan 2016 · RSC Advances
  • Xi Chen · Fu-Quan Bai · Yongan Tang · Hong-Xing Zhang
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    ABSTRACT: The substituent effects on the structures, intermolecular interactions and charge transport properties of a series of corannulene and sumanene derivatives were investigated by DFT method. The intermolecular interaction energy and the potential energy surface of the dimers were also calculated and analyzed in detail, which showed several local energy minima and demonstrated the possible dimer structures in experiment. In addition, the reorganization energy, transfer integral, and carrier mobility were explored to measure the charge transport properties of these substituted corannulenes and sumanenes at different configurations for investigating the substituent effects. Our study is closely related to the experiment and previous theoretical investigation and provides a better understanding of the structure-property relationships for these substituted corannulenes and sumanenes. © 2015 Wiley Periodicals, Inc.
    No preview · Article · Dec 2015 · Journal of Computational Chemistry
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    Yulai Zhang · Qing-Chuan Zheng · Ji-Long Zhang · Hong-Xing Zhang
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    ABSTRACT: Ruminococcus albus cellobiose 2-epimerase (RaCE) and N-acetyl-d-glucosamine 2-epimerase from porcine kidney (pAGE) belong to the AGE superfamily and have a detectable AGE activity. Interestingly, RaCE and pAGE share a set of conserved residues and have a similar catalytic mechanism, although they exhibit different substrate specificities, in that RaCE reacts with unmodified oligosaccharides and pAGE reacts with modified monosaccharides. In this study, the reaction mechanisms of RaCE and pAGE were theoretically calculated by using the quantum mechanics/molecular mechanics method based on the umbrella sampling simulations. The simulation results not only characterize the detailed mechanism of enzyme actions, but also reveal the difference between the catalytic mechanism of RaCE and pAGE. The energy barriers of the two reactions indicate that the activity of reprotonation in the epimerization activities is much higher than that of the deprotonation. Additionally, we obtained the structural information of the transition states of deprotonation and reprotonation and the stable intermediate states and analyzed the enzyme function of lowering the activation energy. Our work can provide important information to understand the catalytic mechanism of the AGE family.
    Full-text · Article · Nov 2015 · RSC Advances
  • Li Wei-Kang · Qing-Chuan Zheng · Hong-Xing Zhang
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    ABSTRACT: TvMyb2, one of the Myb-like transcriptional factors in Trichomonas vaginalis, binds to two closely spaced promoter sites, MRE-1/MRE-2r and MRE-2f, on the ap65-1 gene. However, detailed dynamical structural characteristics of the tvMyb2-ap65-1 complex and a detailed study of the protein in the complex have not been done. Focused on a specific tvMyb2-MRE-2-13 complex (PDB code: ) and a series of mutants K51A, R84A and R87A, we applied molecular dynamics (MD) simulation and molecular mechanics generalized Born surface area (MM-GBSA) free energy calculations to examine the role of the tvMyb2 protein in recognition interaction. The simulation results indicate that tvMyb2 becomes stable when it binds the DNA duplex. A series of mutants, K51A, R84A and R87A, have been followed, and the results of statistical analyses of the H-bond and hydrophobic contacts show that some residues have significant influence on recognition and binding to ap65-1 DNA. Our work gives important information to understand the interactions of tvMyb2 with ap65-1.
    No preview · Article · Nov 2015 · Molecular BioSystems
  • Jiu-Yu Zhan · Ji-Long Zhang · Yan Wang · Ye Li · Hong-Xing Zhang · Qing-Chuan Zheng
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    ABSTRACT: Focal adhesion kinase is an important target for the treatment of many kinds of cancers. Inhibitors of FAK are proposed to be the anticancer agent for multiple tumors. The interaction characteristic between FAK and its inhibitors is crucial to develop new inhibitors. In the present article, we used Molecular Dynamic (MD) simulation method to explore the characteristic of interaction between FAK and three inhibitors (PHM16, TAE226, and ligand3). The MD simulation results together with MM-GB/SA calculations show that the combinations are enthalpy-driven process. Cys502 and Asp564 are both essential residues due to the hydrogen bond interactions with inhibitors, which was in good agreement with experimental data. Glu500 can form a non-classical hydrogen bond with each inhibitor. Arg426 can form electrostatic interactions with PHM16 and ligand3, while weaker with TAE226. The electronic static potential was employed, and we found that the ortho-position methoxy of TAE226 has a weaker negative charge than the meta-position one in PHM16 or ligand3. Ile428, Val436, Ala452, Val484, Leu501, Glu505, Glu506, Leu553, Gly563 Leu567, Ser568 are all crucial residues in hydrophobic interactions. The key residues in this work will be available for further inhibitor design of FAK and also give assistance to further research of cancer.
    No preview · Article · Nov 2015 · Journal of biomolecular Structure & Dynamics
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    ABSTRACT: The molecular self-assembly behaviour of 2,2′-bis-(4-hexyloxyphenyl)-bi-1,3,4-oxadiazole (BOXD-6) in solution, on surfaces and in bulk crystals, and its photo-physical properties were studied via a combination of experimental techniques and theoretical calculations. It is found that BOXD-6 molecules self-assemble into both H- and J-aggregates at moderate concentration (∼10-4 M) and then transit to exclusive J-aggregates at higher concentration (∼10-3 M) in tetrahydrofuran. In H-aggregation (α polymorph), BOXD-6 adopts a linear conformation and forms a one-dimensional layered structure; in J-aggregation (β polymorph), it adopts a Z-shaped conformation and forms a more ordered two-dimensional layered structure. A π-stacking structure is observed in both cases, and adjacent molecules in J-aggregation show larger displacement along the molecular long axis direction than that in H-aggregation. Although J-aggregates are almost the only component in concentrated solutions (10-3 M), both H- and J-aggregates can be obtained if concentrated solution is transformed onto substrates through a simple drop-casting method. Such a phase transition during film formation can be easily avoided by adding water as a precipitator; a film with pure J-aggregates is then obtained. In order to get more information on molecular self-assembly, intermolecular interaction potential energy surfaces (PES) were evaluated via theoretical calculations at the DFT level (M062x/6-31G∗∗). The PES not only confirm the molecular stacking structures found in crystals but also predict some other likely structures, which will be the target of future experiments.
    No preview · Article · Nov 2015 · Journal of Materials Chemistry C
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    Li Hao · Jian Wang · Fu-Quan Bai · Mo Xie · Hong-Xing Zhang
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    ABSTRACT: As a donor type dopant in titanium dioxide, W6+ was found to move the conduction band (CB) edge of TiO2 downward and also to influence the electron-injection process in dye-sensitized solar cells (DSSCs). To investigate the electron-injection capabilities of DSSCs and to optimize their efficiency by W6+ doping, the geometry and electronic properties of both free and adsorbed TiO2 nanowires were investigated on the basis of extensive density functional theory calculations. A four-layer (TiO2)12 nanowire with 12 possible doping sites was set up, and the effect of W6+ in different positions was analyzed. The results indicate that in the W6+-doped (TiO2)12 systems, the Ti-OW (OW = oxygen atom that is connected to the W atom) bonds are longer than the corresponding Ti-O bonds in (TiO2)12. The CB edge is significantly influenced by the doping position. The CB energy level moves upward gradually as doped W6+ moves deep into (TiO2)12. For all adsorbed catechol/(TiO2)12 systems with the W6+ dopant, the LUMO maps are distributed over the layer in which W6+ is doped. The W6+ doping position plays a crucial role in the electron-injection and electron-transport process in DSSCs. Therefore, different positions of W6+ doping in TiO2 would be a feasible strategy to control and improve semiconductor materials to obtain DSSCs with more efficient electron injection. The relationship between the W6+ doping position and the efficiency of dye-sensitized solar cells is analyzed. Doping TiO2 with W results in an increased electron-injection driving force, and this force can be improved gradually by moving the W6+ dopant up toward the surface. The LUMOs are mainly localized and distributed over the layer in which W6+ is doped for all catechol/(TiO2)12 systems.
    Full-text · Article · Nov 2015 · European Journal of Inorganic Chemistry
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    Miao Xie · Jian Wang · Jie Ren · Li Hao · Fu-Quan Bai · Qing-Jiang Pan · Hong-Xing Zhang
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    ABSTRACT: The local electric field formed between dye sensitizers and semiconductor interface is one of key factors to determine the overall performance of dye-sensitized solar cells (DSSCs). Herein, a strategy has been proposed to explore the influence of the local electric field on the functionality of DSSCs of YD2-O-C8 dye via calculating the relevant properties in various electric field strengths. The YD2-O-C8 dye has been systemically studied with density functional theory (DFT) and time-dependent DFT (TD-DFT) for its electronic structure and optical properties in tetrahydrofuran (THF) solution. The absorption spectra are gradually narrowing and blue-shifting while increasing the electric field strength. Two key parameters of the light harvesting efficiency (LHE) and the TiO2 conduction band shift (ΔEcb) have been examined for the YD2-O-C8 sensitized TiO2 system. It is found that it is of great importance to reduce the charge accumulation on the TiO2 film, which lowers the electric field strength and shows the best performance of DSSCs. This study is expected to deepen our understanding of the function of local electric field and the operational principles of the DSSCs for further optimization.
    Full-text · Article · Nov 2015 · Organic Electronics
  • Xiao-Xi Li · Yong Wang · Qing-Chuan Zheng · Hong-Xing Zhang
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    ABSTRACT: Two types of detoxification routes, N-demethylation to form 4-phenyl-1,2,3,6-tetrahydropyridine (PTP) and aromatic hydroxylation to generate 4-(4'-hydroxyphenyl)-1-methyl-1,2,3,6-tetrahydropyridine (MPTP-OH), for 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mediated by Compound I (Cpd I) of cytochrome P450 are investigated theoretically using hybrid density functional calculations. Quantum chemical results reveal that for the N-demethylation, the initial C-H bond activation is achieved via a hydrogen atom transfer (HAT) mechanism. This is followed by a subsequent O-rebound to yield the carbinolamine intermediate. Due to the nature of pericyclic reaction, the generated carbinolamine decomposes in a non-enzymatic aqueous environment with the assistance of water molecules, forming amine and hydrated formaldehyde. For the aromatic hydroxylation, an initial addition of Cpd I to the substrate occurs mainly through a side-on approach with a subsequent proton shuttle to form the phenol product. A comparison of the energy barriers for both routes indicates that the N-demethylation (7.5/5.7kcal/mol for the quartet/doublet state in solvent) is thermodynamically more favorable than the aromatic hydroxylation process (14.9/14.8kcal/mol for the quartet/doublet state in solvent). This trend is in good agreement with the experimental product distribution, viz., the N-demethylation product PTP is more than the aromatic hydroxylation product MPTP-OH. Taken together, these observations not only enrich our knowledge on the mechanistic details of the N-dealkylation and the aromatic hydroxylation by P450s, but also provide certain insights into the metabolism of other analogous toxins.
    No preview · Article · Oct 2015 · Journal of inorganic biochemistry
  • Xin Wang · Fu-Quan Bai · Miao Xie · Li Hao · Hong-Xing Zhang
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    ABSTRACT: The structures and properties of a family of different π-conjugation tetra pyrrole Zn complexes are reported. The tetra pyrrole moiety can be divided as porphyrin, one tripyrrin and one pyrrole, two dipyrrines, one dipyrrin and two pyrroles, and four pyrroles. The Zn complexes possess different geometries and tunable spectral bands depending on the mode of the different metal-coordination. For Zn porphyrin, the frontier molecular orbitals (FMOs) are the major contribution to the intense B-like band and weak Q-like band absorptions, and this is in agreement with the Gouterman’s four-orbital model. But because of the breakdown of the π-conjugation from complex 1 to 5, the FMOs are no longer separated from the other MOs in energy, the orbital with metal distribution is approaching to lowest unoccupied molecular orbital (LUMO), the absorption band is no longer intense at B-like bond and weak at Q-like bond as Gouterman's four-orbital model mentioned. The calculated fluorescence spectra in toluene solution show that fluorescence can be observed in the visible region of complexes 1–4 because of the bright higher electronic excited states.
    No preview · Article · Oct 2015 · Synthetic Metals
  • Xin He · Zeng-Xia Zhao · Hong-Xing Zhang
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    ABSTRACT: In this work, we report performed a high level ab initio study on the low-lying electronic states of C6H5OO, utilizing complete active space self-consistent field (CASSCF) and multiconfiguration second-order perturbation theory (CASPT2) method, and the contracted ANO-L basis set have been taken into account. The potential energy curves for the four lowest states associated with the lowest dissociation limit of C6H5OO radical. The calculated results clearly assigned the experimentally observed photodissociation channels leading to C6H5O (X2A, 22A) + O(3Pg) and C6H5 (X2A) + O2(X3Σg−, 11Δg, 11Σg+).
    No preview · Article · Sep 2015 · Computational and Theoretical Chemistry
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    Li Hao · Jian Wang · Fu-Quan Bai · Miao Xie · Hong-Xing Zhang
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    ABSTRACT: Based on titanium dioxide model and LJBs sensitizers (triphenylamine as the donor, 3,4-ethylene dioxy thiophene plus various functionalized phenylenes as the π-spacer, and cyanoacrylic acid as the anchoring group) with different connection types on TiO2 substrate, the reasonable dye-TiO2 connection has been located. The results show that the dissociative adsorption of LJBs is more thermodynamically favorable than the neutral molecule bound configurations. LJBs adsorb onto TiO2 via interaction between 3d orbital of surface Ti atom and 2p orbital of N/O atoms in the acceptors. This result is confirmed in both neutral and dissociation forms of LJBs molecules. According to our calculations, adding a meta-fluorine substituent to the phenyl group of cyanoacrylic acid (LJB-Fm) may damage the planarity and conjugation. Consequently, the light harvesting efficiency decreased, and that is particularly unfavorable for the DSSCs application. The Ortho F-substituted dye (LJB-Fo), however, exhibited enhanced light absorption and more efficient intra-molecular charge transport. The bigger Jsc, Voc values of LJB-Fo system predicts its superior DSSC performance. Additionally, LJBs anchored on TiO2 surface via group –COO (LJB-H and LJB-Fo) lead to an indirect mechanism for electron injection. While LJB-Fm preferred to direct electron injection mechanism due to the strong orbital-coupling between sensitizer and the TiO2 substrate.
    Full-text · Article · Sep 2015 · Computational and Theoretical Chemistry
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    ABSTRACT: Understanding of reaction and structural property of diuranium(III) complexes of a single ligand is essential to advancing their experimental synthesis and exploring promising applications in small molecule activation chemistry. In this work, we theoretically examined a series of diuranium(III) complexes building on the reaction of [UI3(THF)4] and octadentate polypyrrolic ligands (H4L1 and H4L2). At the relativistic density functional theory level, 11.2 kcal/mol energy is required to form the Pacman-like [(UI)2(μ2-I)(L1)]- (1) in THF solution, while only 0.5 kcal/mol for its non-classic Pacman isomer 1n. These agree with their analogues that have been experimentally proposed. A variety of chemical modification has been made for 1. The addition of one THF solvent or one iodine ion raises reaction energy by 6.8∼14.5 kcal/mol, while two or more are significantly endoergic. Smaller energies of 1.4 and 7.4 kcal/mol are required when varying bridged atom (from the iodine of 1 into the THF of 2 [(UI)2(μ2-THF)(L1)]) and lengthening ligand linker size (from ortho-phenylene of H4L1 of 1 into anthracene of H4L2 of 3 [(UI)2(μ2-I)(L2)]-), respectively. Eleven diuranium(III) complexes were optimized to be energetically stable. The U-U distances of 4.13 and 4.08 Å were calculated for 1 and 2, respectively, compared with the long one of 5.90 Å for 3.
    No preview · Article · Aug 2015 · Inorganica Chimica Acta
  • Qiao Xue · Ying-Lu Cui · Qing-Chuan Zheng · Hong-Xing Zhang
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    ABSTRACT: BioH, an enzyme of biotin synthesis, plays an important role in fatty acid synthesis which assemble the pimelate moiety. Pimeloyl-acyl carrier protein (ACP) methyl ester, which is long known to be a biotin precursor, is the physiological substrate of BioH. Azelayl methyl ester, which has a longer chain than pimeloyl methyl ester, conjugated to ACP is also indeed accepted by BioH with very low rate of hydrolysis. To date, the substrate specificity for BioH and the molecular origin for the experimentally observed rate changes of hydrolysis by the chain elongation have remained elusive. To this end, we have investigated chain elongation effects on the structures by using the fully atomistic molecular dynamics simulations combined with binding free energy calculations. The results indicate that the substrate specificity is determined by BioH together with ACP. The added two methylenes would increase the structural flexibility by protein motions at the interface of ACP and BioH, instead of making steric clashes with the side chains of the BioH hydrophobic cavity. On the other hand, the slower hydrolysis of azelayl substrate is suggested to be associated with the loose of contacts between BioH and ACP, and with the lost electrostatic interactions of two ionic/hydrogen bonding networks at the interface of the two proteins. The present study provides important insights into the structure-function relationships of the complex of BioH with pimeloyl-ACP methyl ester, which could contribute to further understanding about the mechanism of the biotin synthetic pathway, including the catalytic role of BioH.
    No preview · Article · Jul 2015 · Journal of biomolecular Structure & Dynamics
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    Peng Fu · Ran Jia · Chui-Peng Kong · Roberts I Eglitis · Hong-Xing Zhang
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    ABSTRACT: The equation of state (EOS) from virial expansion (VE) is used in this work to pave the way for determining the fugacity coefficients of the hydrogen fluid at arbitrary temperature and pressure. The fugacity coefficients from our VE method have more physical meanings than the empirical values. In this way, the hydrogen storage capacity of a novel material model can be estimated by using few density functional theory (DFT) calculations with the aid of a continuum model. The efficient continuum model can provide a more accurate estimation of the hydrogen storage capacity than the pure DFT calculations. Furthermore, the expensive grand canonical ensemble (mNT) simulations combining with the quantum mechanics methods (i.e., QM/MD-mNT) are unnecessary within this method. The hydrogen fluid can be handled with our VE method at the temperature in the range of 160e773 K. The hydrogen storage capacity and the detailed thermodynamic information of a designed novel material can thereby be estimated by using this method with relatively high accuracy and low computing cost. As an example, the hydrogen storage capacities of the expanded bilayer graphene systems are presented. Our theoretical results agree with the experimental values very well.
    Full-text · Article · Jul 2015 · International Journal of Hydrogen Energy
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    ABSTRACT: The photophysical properties of 2,2′-bis-(4-alkoxyphenyl)-bi-1,3,4-oxadiazole (BOXD-n), have been studied by a combination of spectroscopic techniques and theoretical calculations. Interestingly, strong fluorescence red-shift in polar solvents was observed in this highly symmetric molecule, which indicates an efficient charge transfer (CT) occurred in the excited state. The change of molecular dipole moment between the ground state and CT excited state was calculated to be 9.9 D. Theoretical calculations at Density Functional Theory level revealed that the first singlet excited state of BOXD-n shows both π-π∗and CT characters. Clear evidence for charge transfer from alkoxy benzene to the central bi-1,3,4-oxadiazole group can be observed by analysing the atomic charge and electron density change, though it is not significant. Since BOXD-1 retained a planar conformation and became more quinoid-like in the excited state, a planar intramolecular charge transfer is assigned for it. By further comparing these results with the half molecule terminated by CH3 group (2-tetradecyloxyphenyl, 5-methyl-1,3,4-oxadiazole), it could be concluded that intramolecular charge transfer property was enhanced in this DAAD arrangement of BOXD-n.
    No preview · Article · Jul 2015 · Journal of Photochemistry and Photobiology A Chemistry
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    ABSTRACT: Cytochrome P450 (CYP) 3A7 plays a crucial role in the biotransformation of the metabolized endogenous and exogenous steroids. To compare the metabolic capabilities of CYP3A7-ligands complexes, three endogenous ligands were selected, namely, dehydroepiandrosterone (DHEA), estrone and estradiol. In this study, a three-dimensional model of CYP3A7 was constructed by homology modeling using the crystal structure of CYP3A4 as the template and refined by molecular dynamics simulation (MD). The docking method was adopted, combined with MD simulation and the Molecular Mechanics Generalized Born Surface Area (MM-GB/SA) method, to probe the ligand selectivity of CYP3A7. These results demonstrate that DHEA has the highest binding affinity, and the results of the binding free energy were in accordance with the experimental conclusion that estrone is better than estradiol. Moreover, several key residues responsible for substrate specificity were identified on the enzyme. Arg372 may be the most important residue as the low interaction energies and the existence of hydrogen bond with DHEA throughout simulation. In addition, a cluster of Phe residues provides a hydrophobic environment to stabilize ligands. The present study provides insights into the structural features of CYP3A7, which could contribute to further understanding of related protein structures and dynamics.
    No preview · Article · Jun 2015 · Journal of biomolecular Structure & Dynamics