A temperature-jump apparatus with laser light sources was used to investigate the binding mechanism of indium(III) to pyrocathecol violet (3,3‘,4‘- trihydroxyfuchsone-2-sulfonic acid, whose neutral form is denoted as H4L). Spectrophotometric measurements revealed that for [H+] > 0.015 M, the main bound species are MH3L2+ and MH2L+ whereas for [H+] < 0.015 M, the main bound species is M2L2+. Two relaxation
使用带有激光光源的温度跳跃装置来研究
铟 (III) 与
邻苯二酚紫(3,3',4'-三羟基fuchsone-2-
磺酸,其中性形式表示为 H4L)的结合机制。分光光度测量表明,对于 [H+] > 0.015 M,主要结合物质是
MH3
L2+ 和
MH2L+,而对于 [H+] < 0.015 M,主要结合物质是 M2L2+。观察到两种放松效果。快速弛豫主要与反应步骤 M3+ + H3L- ↔ MH3L2+ (k2 = 1.2 × 106 M-1 s-1, k-2 = 1.5 × 105 s-1) 和 MOH2+ + H3L- ↔ MH2L+ (k3 = 4.4 × 107 M-1 s-1,k-3 = 7.4 × 102 s-1)。随着离子强度的增加,速率常数 k2 降低,而 k-2 增加。添加 Na2SO4 导致快速弛豫时间大大减少,这是由于铟 (III) 与硫酸盐的结合。分析弛豫时间对
硫酸盐浓