A single crystal EPR study of the platinum (III)-bis (maleonitriledithiolate)-monoanion

Abstract

A first single crystal EPR study of a Pt3+ chelate-tetrabutylammonium-bis (maleonitriledithiolato) platinate (III)-diamagnetically diluted by the corresponding gold (III) chelate is reported. The spectra are described by a rhombic spin Hamiltonian. For some orientations of the magnetic field 33S superhyperfine splitting was observed. The 33S tensor has the maximum value perpendicular to the plane of the complex supporting a 2B3g ground state in which the half-filled out-of-plane π molecular orbital is extensively delocalized over the ligands. Furthermore, the electron spin-lattice relaxation of the Pt3+ complex was measured in the temperature range 4.2 ≤ T ≤ 16 K. Spin-lattice interactions were found to be mainly responsible for the linewidth in the Pt3+ spectra, which is larger by a factor 2 than those observed for Pd3+ and Ni3+ in the same host complex [Au(mnt)2]-. © 1977.