Theoretical Studies on the Reaction Mechanism of AsCl_3 with H_2 in the Vapor Phase Epitaxy of GaAs

The reaction mechanism of AsCl3 with H2 has been studied by using the method of BHandHLYP in Density Functional Theory (DFT) at the 6-311G** basis set. The transition state of each reaction is verified via the analysis of vibration mode and Intrinsic Reaction Coordinate (IRC). Meanwhile,single-point energy has been calculated at the QCISD(T)/6-311G** level,and the zero-point energy correction has been made to the total energy and reaction energy barrier. It shows that AsCl3 reacts with H2 to first result in AsHCl2 which may incline to self-decompose and finally afford the product As2,or continue to react with H2 to provide the product AsH3. The computing result demonstrates that the former is the main reaction channel.     

Quantum-chemical Study on the Structures and Properties of Uracil-BX3 （X = F, Cl） Complexes

1 INTRODUCTION The intermolecular interaction of bases in DNA or RNA is of immense interest and significance to che- mists and biologists alike. The interactions of these bases with metal cations, solvent molecules and other small molecules or ions would affect the struc- ture and biological properties or recognition process,which has been investigated widely[1～8]. Boron contained compounds are electron deficient com- pounds and have been extensively used as catalysts in chemical react…     

Fabrication of Two-dimensional Monolayer and One-dimensional Wire of Zn-tetra-[3,5-di-t-butylphenyl]-porphyrin on Cu(100) Surface

1 INTRODUCTION Metalloporphyrins and their derivatives having been intensively studied play an important role in biological processes, such as oxygen transport and photosynthesis. They can act as catalysts[1] and un- dergo reversible redox reactions in which the site of electron transfer may be localized on the porphyrin ring or the central metal ion. Both reactions are important in natural processes[2]. Recently, it hasbecome known that structural distortion from planar geometry is fairl…     

Crystal Structure of Lithium Yttrium Borate LiY6O5（BO3）3

1 INTRODUCTION In recent years, more and more attention has been paid to rare-earth borates due to their excellent pro- perties, such as YCa4O(BO3)3(YCOB)[1], YAl3(BO3)4 (YAB)[2] and La2CaB10O19[3] for nonlinear optical materials and self-frequency doubling materials as well as YBO3:Eu for red phosphor materials[4] and Li6M1-xCex(BO3)3 (M = Y, Gd) for neutron detec- tors[5]. In this work, we focus our research interest on LiY6O5(BO3)3 as hosts for VUV (vacuum ultraviolet) l…     

Synthesis and Crystal Structure of a Two-dimensional Zinc(II) Coordination Polymer: [Zn_2(DTB)(DMF)_4(H_2O)_2]_n (DTM= 1,4-Dinitro-2,3,5,6-tetracarboxylatebenzene Tetravalent Anion; DMF = Dimethylformamide)

1 INTRODUCTION For a long time much research interest has beenfocused on coordination polymers because they mayafford new materials with useful properties, such ascatalytic activity, microporosity, electrical conduc-tivity, non-linear optical activit…     

Estimation of n-Octanol/water Partition Coefficients （lgKow） and the Aqueous Solubility （-lgSw） of all PCDF Congeners by Density Functional Theory

1 INTRODUCTION As is widely known, PCDFs together with poly- chlorinated dibenzo-p-dioxins (PCDDs) and poly- chlorinated biphenyls (PCBs) have been included in many blacklists, such as “persistent organic pol- lutants (POPs)” and suspected “environmental en- docrine disruptors (EEDs)”. This is because PC- DFs are chemically and thermally stable and com- plex PCDF mixtures are generally resistant to bio- degradation. Although the concentration of these chemicals is quite low o…     

Synthesis and Molecular Structure of Acetic Acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester

1 INTRODUCTION Quinoxaline derivatives have broad applica- tions in dye, medicine, polymer materials and so on, such as the active red Levafix. In recent years, quinoxaline derivatives are found to show great effects in anticancer, anthelmintic, antibacterial and therapy of HIV[1～3]. Glycosides are the most important forms of sugars in nature, and chemists have synthesized O-glycosides, N-glycosides, S- glycosides, C-glycosides, etc.[4～8] Glycosides also have anticancer and anthelmin…     

Synthesis, Characterization, Crystal Structure and Antibacterial Activities of a Nickel(Ⅱ) Complex with 2'-(2-Thienylidene)-hydroxybenzoylhydrazide

In the ethanol solvent, a nickel(II) complex Ni(C12H10N2O2S)2 upon reaction of 2'-(2-thienylidene)-hydroxybenzoylhydrazide with nickel acetate was synthesized, and its structure was characterized by IR, UV, elemental analysis and X-ray diffraction analysis. The crystal belongs to monoclinic system, space group C2/c with a = 22.052(3), b = 5.9681(6), c = 18.522(2) , β = 110.679(4)°, V = 2280.6(4) 3, Z = 4, Mr = 551.27, μ = 1.606 mm-1, Dc = 1.075 g/cm3, F(000) = 1136 and Rint = 0.0556. The nickel(Ⅱ ) atom in the compound is four-coordinated with two nitrogen atoms from amide and two oxygen atoms from keto group. The biological activities have been measured, show- ing the compound exhibits better anti-bacterial activity than the ligand.     

Synthesis and Structure of anti-Configuration Complex [Cu(tssb)_2]·2[(H_3O)Cl]·4H_2O

1 INTRODUCTION The complexes of amino acid Schiff base have attracted considerable attention because of their bio- activities[1, 2]. Taurine is a special amino acid in be- ings, and recently the complexes of taurine conden- sation salicylaldehyde Schiff …     

Synthesis and Crystal Structure of Tetraaquacopper(II) Bis(5-fluorouracil-1-acetate) Tetrahydrate

1 INTRODUCTION 5-Fluorouracil (5-FU) is an antimetabolite with good antimicrobial and antitumor activities but has toxic side effects[1~4]. In order to improve the topical delivery of 5-FU and reduce the side effects, many derivatives of 5-FU have been synthesized, some of which are of improved activity. 5-Fluorou- racil-1-acetic acid is a member of the family[5~8], which belongs to the pyrimidine base and is a cyto-toxic analogue of the natural base thymine, and has proven useful in th…