Synthesis and characteriza-tion of two new types of oxovanadium complexes with pyrazole as ligand

作     者：XING Yongheng ZHANG Yuanhong XU Yongting ZHANG Baoli NIU Shuyun BAI Fengying 

作者机构：Bioinorganic Laboratory Liaoning Normal University Dalian 116029 China Experiment Center Liaoning Normal University Dalian 116029 China Department of Life Science Liaoning Normal University Dalian 116029 China 

出 版 物：《Chinese Science Bulletin》 (中国科学通报)

年 卷 期：2006年第51卷第18期

页      面：2189-2196页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 070304[理学-物理化学(含∶化学物理)] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 

基　　金：the National Natural Science Foundation of China (Grant No. 20571036), SPF(2004-2007) for R0CS SEM and Education Foundation of Liaoning Province (Grant No. 05L212) 

主　　题：吡唑 晶体结构 非等温动力学分解 C3H4N2 合成 配位子 

摘      要：At room temperature, two new different oxovanadium complexes with simple pyrazole (C3H4N2) as ligand were synthesized. VO(pz)4(SO4)? H2O (1) (pz: pyrazole) is a mono-nuclear oxovana- dium complex with pyrazole as terminal ligands. V2O2(μ-pz)(μ-OOSO2)(μ-OCH3)(pz)4 (2) is bi-nuclear oxovanadium complex containing three different bridges, which are pyrazolate, sulphate and methoxy, respectively. The two complexes were characterized by IR, elemental analyses, thermal analyses and X-ray diffraction. The crystal structural data of the complexes 1 and 2 are given as follows: Complex 1, orthorhombic, Pna21, a = 14.547(2) ?, b =10.895(2) ?, c =11.835(2) ?; α=β=γ=90°, V=1875.8(5) ?3, Z = 4, R1 = 0.0485, WR2 = 0.1092. Complex 2, triclinic, P1 , a =8.377(2) ?, b =9.928(2) ?, c = 16.527(3) ?, α = 85.54(3)°, β = 80.92(3)°, γ = 87.92(3)°, R1 = 0.1461, WR2 = 0.4444. The study of non-thermal kinetic de- composition shows that, for complex 1, the possible reaction mechanisms of the two steps are nucleation and growth n=1/3, and three-dimensional pervasion n=2, respectively, and the kinetic equations may be expressed as dα/dT = (A/β)exp(?E/RT){1/3(1?α) [?In(1?α)]?2} and dα/dT = (A/β)exp(?E/RT){3/2(1?α)2/3 [1?(1?α)1/3] ?1}, respectively; for complex 2, the pos- sible reaction mechanisms of the two steps are chemical reaction, and three-dimensional pervasion n=2, respectively; the kinetic equations may be ex- pressed as dα/dT = (A/β)exp(?E/RT)[(1?α)2], anddα/dT = (A/β)exp(?E/RT){3/2(1?α)2/3[1?(1?α)1/3] ?1}, respectively.