The single-crystal electronic and e.s.r. spectra and magnetic susceptibility of monoethylenediaminecopper(II) dichloride

Abstract

The single-crystal polarised electronic spectra, e.s.r. spectra, and magnetic anisotropy of monoethylenediaminecopper(II) dichloride have been measured. These properties suggest that the principal electronic axis coincides with the axis of a distorted tetragonal environment rather than with the axis of the approximate C2 ligand-field symmetry. The electronic spectra have been observed in the [100], [001], and [010] faces and assigned in D2 symmetry with a 2A type ground-state. The sequence of one-electron energy levels has been determined as dx2–y2 > dxy > dz2∼dxz∼dyz. Expressions are derived for the g-values of the copper(II) ion in crystal fields of D2 and C2 symmetry. From the e.s.r. and electronic spectra the combined orbital reduction parameters k⊥ and k∥ have been determined as 0·672 and 0·684 respectively.