A kinetic study of pyrophosphate and peroxodiphosphate complexation of oxovanadium(IV) ion
作者:M.R. Hoffmann、R.A. Stern、P.H. Rieger、J.O. Edwards
DOI:10.1016/s0020-1693(00)91092-2
日期:1976.1
complex, VO(H_2P_2O_7), determined spectrophotometrically in acidic 1.0 M NaClO_4 solution, is logK = 4.4±0.1 at 25°C. The kinetics of the complexation of vanadyl ion by pyrophosphate and peroxodiphosphate were studied at pH 2.0 using stopped-flow spectrophotometry. The reactions are first-order in ligand and in vanadyl ion with rate constants k_2 = 2.3×10^4 and 7.5×10^3 M^(−1) sec^(−1) at 12°C for H_2P_2O_7^(2−)
在酸性1.0 M NaClO_4溶液中用分光光度法测定的钒氧焦磷酸盐配合物VO(H_2P_2O_7)的形成常数在25°C下为logK = 4.4±0.1。使用停止流分光光度法研究了在pH 2.0时焦磷酸和过二磷酸与钒氧离子络合的动力学。对于H_2P_2O_7 ^(2- )和H_2P_2O_8 ^(2-)。络合反应之后是归因于聚合的较慢的次级过程。络合反应的结果与形成单齿复合物的交换机制一致,随后快速闭合螯合环。过二硫酸盐,在类似条件下进行的研究,