ESR spectroscopy of Co2+ impurities in Cd2P2S6 and Cd2P2Se6

Abstract

The ESR spectra of Co2+ impurities in Cd2P2S6 and Cd2P2Se6 are reported. The Co2+ ion is an S=3/2 ion and substitutes for Cd2+ (S=0) ions in the Cd2P2X6 crystal. The spin Hamiltonian parameters g and A were determined using an effective spin=1/2. For Cd2P2S6, g/sub ///=4.86, A/sub ///=440 MHz, gperpendicular to =4,01 and Aperpendicular to =346 MHz. For Cd2P2Se6, g/sub ///=4.98, A/sub ///=565 MHz, gperpendicular to =3.85 and Aperpendicular to =250 MHz. From the temperature dependence of the linewidth, the zero-field splitting, 2D, for Co2+ doped into Cd2P2S6 is estimated to be 127 cm-1. The individual hyperfine lines of Co2+ doped into Cd2P2Se6 show superhyperfine structure due to 77Se(I=1/2, 7.58% natural abundance). This additional splitting is consistent with some covalent bonding between the Co2+ and its six selenium ligands.