A spectroscopic study of some transition-metal ions in acetic acid, in acetate glass and melt, and in nitrate glass

Abstract

A comparison of the d–d spectra of some first-row transition-metal ions in Li(CH₃·CO₂)–Na(CH₃·CO₂) glass and melt is made with the spectra of the same ions in glacial acetic acid. In the glass, chromium(III), nickel(II), and vanadium(IV)(as VO²⁺) are octahedrally co-ordinated, while cobalt(II) and possibly copper(II) have a distorted dodecahedral co-ordination. Although some of the ions, e.g., Cu²⁺ and Cr³⁺, exist as polynuclear species in acetic acid, there is no evidence for this in the acetate glass or melt. Spectra for cobalt(II), nickel(II), and copper(II) in KNO₃–Ca(NO₃)₂ glass are also reported and comparison is made with these ions in the acetate glass.