Notes. Electron spin resonance parameters for some copper(II)–bis(amino-acid) complexes

Abstract

The presence of two components, presumably cis and trans isomers, was previously indicated by the 14N superhyperfine structure pattern in the e.s.r. spectra of a number of copper(II)–bis(amino-acid) complexes in aqueous solution. In the present work the g and hyperfine values of the individual species have been obtained from spectra of the ⁶³Cu and ⁶⁵Cu isotopes. Significantly different values have been observed for the two components and these differences are discussed in terms of possible deviations from the ideal square-planar structure in the cis and trans isomers.