Chemical speciation of L-proline complexes of Ca(II), Zn(II) and Mn(II) in acetonitrile-water mixtures

Abstract

Chemical speciation of binary complexes of Ca(II), Zn(II) and Mn(II) with L-proline is investigated pH-metrically in acetonitrile-water mixtures. The stability constants are calculated using the computer program MINIQUAD75. The best-fit chemical models are selected based on statistical parameters and residual analysis. The models for the binary species contained ML + , MLH 2+ and ML 2 H + for Ca(II), Zn(II) and Mn(II). The trend in variation of stability constants with change in the dielectric constant of the medium is explained on the basis of structure forming nature of acetonitrile. Distribution of the species with pH at different variations (0.0-60.0% v/v) in acetonitrile-water mixtures is also presented.

Computer-augmented modeling studies of Pb(II) and Cd(II) complexes with maleic acid in ethylene glycol–water mixture

“…[5] Hence, the chemical speciation of ligands with metal ions has been studied in this laboratory. [6][7][8][9][10] Maleic acid is a dicarboxylic acid. It is the cis isomer of butenedioic acid, whereas fumaric acid is the trans isomer.…”

Speciation of ternary complexes of Ca(II), Zn(II) and Mn(II) with L-proline and L-valine in acetonitrile–water mixtures

“…Stability constants of their binary complexes with Ca(II), Zn(II) and Mn(II) in AN-water mixtures were communicated (Veeraswami et al, 2013). The present study deals with the stability constants of the ternary complexes of Ca(II), Zn(II) ) (Qualigens, India) solution was used to maintain 0.16 mol L -1 ionic strength in the titrand.…”