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	1. The Use of Fluorinated Hydrocarbons as Reference Standards in 19F NMR Calculation
	Yang Miyi,Li Songqing,Gao Haixiang,Zhou Wenfeng
	Chemistry 27 December 2012
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	Abstract:A new method to improve the precision of fluorine nuclear magnetic resonance (NMR) calculations of reference standards was studied using different quantum chemistry methods and basis sets on a large number of compounds, which are widely used and possess well-known chemical shifts. After comparing the calculated data and experimental results, we found that perfluoroethane and 4-fluorostyrene are suitable reference standards for fluorine atoms bonded to sp3 and sp-sp2 carbons, respectively. In our final experiments, we used the PBEL/6-311++ (3df, 2pd)//B3LYP/6-31G (d, p) level of theory and the above two compounds as reference standards for the final optimized method. This novel method creates new paradigms for NMR shift calculations and has increased the calculation precision and accuracy.
	TO cite this article:Yang Miyi,Li Songqing,Gao Haixiang, et al. The Use of Fluorinated Hydrocarbons as Reference Standards in 19F NMR Calculation[OL].[27 December 2012] http://en.paper.edu.cn/en_releasepaper/content/4508294


	2. First-principles study of pressure effects on structural and absorption properties of crystalline 5-methyl-1H-tetrazole
	ZHU Weihua
	Chemistry 21 August 2011
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	Abstract:A detailed study of the structural, electronic, and absorption properties of crystalline crystalline 5-methyl-1H-tetrazole under hydrostatic pressure of 0-100 GPa was performed with density functional theory. The results show that the structure is much stiffer in the c direction than along the a and b axes, showing that the compressibility of 5-methyl-1H-tetrazole crystal is anisotropic. As the pressure increases, the band gap gradually decreases; moreover, the gap reduction is more pronounced in the low-pressure range compared to the high-pressure region. An analysis of density of states shows that the electronic delocalization in 5-methyl-1H-tetrazole gradually increases under the influence of pressure. An understanding of the stabilities of 5-methyl-1H-tetrazole under compression based on the electronic structure shows that an applied pressure increases the impact sensitivity of 5-methyl-1H-tetrazole to detonation initiation. As the pressure increases, 5-methyl-1H-tetrazole has relatively high optical activity. The absorption spectra of 5-methyl-1H-tetrazole at high pressure display a few, strong bands in the fundamental absorption region.
	TO cite this article:ZHU Weihua. First-principles study of pressure effects on structural and absorption properties of crystalline 5-methyl-1H-tetrazole[OL].[21 August 2011] http://en.paper.edu.cn/en_releasepaper/content/4439870

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	3. Periodic DFT study of crystalline 1,5-disubstituted 1H-tetrazole derivatives
	ZHU Weihua,XIAO Heming
	Chemistry 19 December 2010
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	Abstract:In this paper, we firstly determined the crystal structures of 1,5-disubstituted 1H-tetrazole derivatives: 1,5-dimethyl-1H-tetrazole, 1,5-diazido-1H-tetrazole, 1,5-diamino-1H-tetrazole, and 1,5-dinitro-1H-tetrazole. Then, we performed periodic density functional theory calculations to study the electronic structure and absorption spectra of crystalline 1,5-disubstituted 1H-tetrazole derivatives. An analysis of electronic structure shows that the four crystals have good electronic delocalization and the ring for them may be firstly broken in the thermal decomposition. The absorption spectra of the four crystals display a few strong bands in the fundamental absorption region. Finally, the impact sensitivity order of the four crystals was predicted based on their band gaps.
	TO cite this article:ZHU Weihua,XIAO Heming. Periodic DFT study of crystalline 1,5-disubstituted 1H-tetrazole derivatives[OL].[19 December 2010] http://en.paper.edu.cn/en_releasepaper/content/4399047


	4. A Frist-principles Study of the Charge-transfer Parameters in Dithiophene-tetrathiafulvalene(DT-TTF) crystal
	Zhang Weiwei,Liang Wanzhen,Zhao Yi
	Chemistry 12 May 2010
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	Abstract:The parameters controlling charge-transfer, reorganization energy and electronic coulping, in the Dithiophene-tetrathiafulvalene (DT-TTF) crystal have been inverstigated on the basis of a density functional theory (DFT). The results reveal that only several high-frequency intramolecular vibrational modes dominate the reorganization energy from the mode-specific analysis. The electronic couplings obtained from the reduced two-states model (TM) are differences obviously for different types of the dimers. Meanwhile, the electronic couplings of isolated DT-TTF dimers are affected by the surrounding molecules in crystal. Furthermore, the nulcear-coordinate dependence of electronic coupling prefers to perform an exponential or Gaussian property for most intermolecular modes rather than a linear one .
	TO cite this article:Zhang Weiwei,Liang Wanzhen,Zhao Yi. A Frist-principles Study of the Charge-transfer Parameters in Dithiophene-tetrathiafulvalene(DT-TTF) crystal[OL].[12 May 2010] http://en.paper.edu.cn/en_releasepaper/content/4371919


	5. Isomerization of B6, B6– and B6+ clusters
	Wei Gongmin,Pu Zhifeng,Zou Rong,Li Guoliang,Luo Qiong
	Chemistry 10 March 2010
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	Abstract:The isomerizations between isomers with same spin multiplicity of neutral B6, charged B6+ and B6– clusters were investigated at the B3LYP/6-311+G* level of theory, including the minimum energy pathways with the transition states connecting the corresponding reactants and products. In dynamic calculation, twenty-six isomers were optimized, including eleven novel isomers. In order to further refine the energies, single-point B3LYP/6-311+G(3df) calculations were carried out on the corresponding B3LYP/6-311+G* geometries of all isomers of B6, B6+, B6－ and the corresponding isomerization transition states. The stability of each isomer of B6 (singlet and triplet states), B6+ (doublet state) and B6－(doublet state) were analyzed from both thermodynamic and dynamic viewpoints.
	TO cite this article:Wei Gongmin,Pu Zhifeng,Zou Rong, et al. Isomerization of B6, B6– and B6+ clusters[OL].[10 March 2010] http://en.paper.edu.cn/en_releasepaper/content/40550


	6. Structures and Electronic Properties of Peanut-Shaped Dimers and Nanotubes Consisted of C50 Cages
	Bai Hongcun,Qiao Weiye,Wang Guo,Huang Yuanhe
	Chemistry 18 January 2010
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	Abstract:The structures and electronic properties of the peanut-shaped dimers and nanotubes consisted of C50 cages are investigated based on the ab initio self-consistent field molecular and crystal orbital calculations. It is found that the formation of peanut-shaped dimers is energeticlly favorable. The corresponding peanut-shaped nanotubes are semiconductors due to existence of the energy gaps. These peanut-shaped nanotubes are predicted to have smaller Young moduli than the single-walled carbon nanotube. The anionic peanut-shaped nanotubes are also calculated in this paper, as well as the infrared spectra of the peanut-shaped dimers.
	TO cite this article:Bai Hongcun,Qiao Weiye,Wang Guo, et al. Structures and Electronic Properties of Peanut-Shaped Dimers and Nanotubes Consisted of C50 Cages[OL].[18 January 2010] http://en.paper.edu.cn/en_releasepaper/content/39103


	7. Size Effects for the Adsorption of Alkali Metal Atoms on the Si(001) Surface
	Cai Yaping,Li Yi,Zhang Yongfan
	Chemistry 06 July 2009
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	Abstract:The adsorptions of a series of alkali metal (AM) atoms, Li, Na, K, Rb and Cs on a Si(001)-2x2 surface at 0.25 monolayer coverage have been investigated systematically by means of density functional theory calculations. The effects of the size of AM atoms on the Si(001) surface are focused in the present work by examining the most stable adsorption site, diffusion path, band structure, charge transfer, and the change of work function for different adsorbates. Our results suggest that, when the interactions among AM atoms are neglectable, these AM atoms can be divided into three classes. For Li and Na atoms, they show unique site preferences, and correspond to the strongest and weakest AM-Si interactions, respectively. In particular, the band structure calculation indicates that the nature of Li-Si interaction differs significantly from others. For the adsorptions of other AM atoms with larger size (namely, K, Rb and Cs), the similarities in the atomic and electronic structures are observed, implying that the atom size has little influence on the adsorption behavior for these large AM atoms on the Si(001) surface.
	TO cite this article:Cai Yaping,Li Yi,Zhang Yongfan. Size Effects for the Adsorption of Alkali Metal Atoms on the Si(001) Surface[OL].[ 6 July 2009] http://en.paper.edu.cn/en_releasepaper/content/33661


	8. Synthesis, Crystal Structure and Theoretical Calculation of DNAZ•NTO
	Li Zhaona,Ma Haixia,Yan Biao,Guan Yulei,Song Jirong
	Chemistry 16 January 2009
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	Abstract:DNAZ•NTO was prepared by mixing 3,3-dinitroazetidine(DNAZ) and 3-nitro-1,2, 4-triazol-5-one (NTO) in ethanol solution. Single crystals suitable for X-ray measurement were obtained. DNAZ•NTO crystallizes in the monoclinic system, space group P21/n with unit cell parameters of a = 1.4970 (4) nm, b =0.6325 (2) nm, c =2.2347 (7) nm,β=96.55 (1), V = 2.1022(11) nm3 , Z = 8. Based on the analysis of the molecule structure, the theoretical investigation of the title compound was carried out with B3LYP method on 6-311++G(**) basis set, and the natural atomic charge and bond orbital analyses were also performed.
	TO cite this article:Li Zhaona,Ma Haixia,Yan Biao, et al. Synthesis, Crystal Structure and Theoretical Calculation of DNAZ•NTO[OL].[16 January 2009] http://en.paper.edu.cn/en_releasepaper/content/27965


	9. Metal-Phosphorus Bonding in Complexes W@Au12PX3 (X = H, F, Cl, Br, I) - Relativistic DFT Investigations
	Jia Li,Yi-Xiang Qiu,Shu-Guang Wang
	Chemistry 04 January 2009
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	Abstract:Relativistic density functional theory (DFT) calculations of the geometries and Au–P bonding of W@Au12PX3 (X = H, F, Cl, Br, I) have been carried out. There are some regular changes in geometry and binding of these two kinds of complexes with the variation of the phosphanes PX3. The energy decomposition analysis confirms that the PX3 ligands are σ donors. The donor tendency (ΔEσ/ΔEπ) decreases for different X with increasing electro negativity.
	TO cite this article:Jia Li,Yi-Xiang Qiu,Shu-Guang Wang. Metal-Phosphorus Bonding in Complexes W@Au12PX3 (X = H, F, Cl, Br, I) - Relativistic DFT Investigations[OL].[ 4 January 2009] http://en.paper.edu.cn/en_releasepaper/content/27242


	10. Electron Attachment to the DNA Bases Adenine and Guanine and Dehydrogenation of Their Anionic Derivatives: A Density Functional Study
	Xie Hujun ,Cao Zexing
	Chemistry 19 October 2006
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	Abstract:Density functional calculations have been used to explore electron attachment to the purines adenine and guanine and their hydrogen atom loss. Calculations show that the dehydrogenation at the N9 site in the adenine and guanine transient anions is the lowest-cost channel of hydrogen loss, and the N9-H bond scission has Gibbs free energies of dissociation 兇G刟 of 8.8 kcal mol-1 for the anionic adenine and 13.9 kcal mol-1 for the anionic guanine. The relatively high feasibility of low-energy electron-induced N9-H bond cleavage in the purine nucleobases arises from high electron affinities of their H-deleted counterparts. Unlike adenine, other N-H bond dissociations are competitive with the N9-H bond fission in the anionic guanine. The replacement of hydrogen in the ring of purine has a significant effect on the N9-H bond fragmentation.
	TO cite this article:Xie Hujun ,Cao Zexing. Electron Attachment to the DNA Bases Adenine and Guanine and Dehydrogenation of Their Anionic Derivatives: A Density Functional Study[OL].[19 October 2006] http://en.paper.edu.cn/en_releasepaper/content/8824

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