作者:Plinio Di Bernardo、Giuliana Tomat、Pierluigi Zanonato、Roberto Portanova、Marilena Tolazzi
DOI:10.1016/s0020-1693(00)83971-7
日期:1988.5
Abstract The stability constants and the heats of formation of vanadyl(IV)—acetate, —glycolate, and —glycine complexes have been determined in aqueous solution by means of potentiometric and calorimetric measurements. In the pH range where the protolitic equilibria of VO 2+ is certainly negligible the acetate forms two mononuclear complexes, the glycolate three whereas the glycine reacts in its zwitterionic
摘要通过电位和量热法测定了水溶液中乙酸(钒)-乙酸,-乙醇酸和-甘氨酸配合物的稳定常数和形成热。在VO 2+的原生质平衡可以忽略不计的pH范围内,乙酸盐形成两个单核络合物,乙醇酸酯形成三个单核络合物,而甘氨酸以其两性离子形式反应。乙醇酸酯配合物的稳定性尽管比碱度低,但仍远高于乙酸盐,表明配合物的形成涉及羟基与金属离子的配位。焓变化是正的,但乙醇酸的负值很小。对于所有系统,熵的变化都是正的,因此有利于复合物的形成。