Vibrational spectroscopic study of the interaction of metal ions with diethyl phosphate, a model for biological systems

Abstract

We have studied, using Raman and infrared spectroscopy, the interaction of various monovalent, divalent, and trivalent metal cations with the [Formula: see text] group of diethyl phosphate in aqueous solution, at metal: phosphate ratios ranging from 1:40 to 6:1. The results show that the metal cations interact with the phosphate groups in various ways and to different extents. Spectral characteristics for some specific types of interactions are presented, namely, for direct metal binding by one of the oxygen atoms in the [Formula: see text] group, the formation of water-separated ion pairs, and non-specific electrostatic interactions.