Electron spin lattice relaxation in some metal dithiolence matrices with ⁶³Cu(II) centres

Abstract

Temperature dependence of the electron spin-lattice relaxation time T₁, of ⁶³Cu doped metal dithio;ene matrices were studied by coninuous wave and time-domain EPR methods. Measurements were made in the temperture range from 10-300K for (n-Bu₄N)₂ Pt(dtsq), (n-Bu₄N)₂ Pt(dcmdtcroc)2, (n-Bu₄N₂ Pd(dtcroc)₂ and (n-Bu₄N)₂ 'Ni(mnt)₂ Matrices where (dtsq) is dithiosquarate (dcmdtcroc) is dicyanomethylinedithiocrocanate, (dtcroc) is dithiocrocanate and (mnt) is maleonitriledithiolate. In all systems T₁ seems to be of the order of a few μs above 80K. In (n-Bu₄N)₂[⁶³Cu/Pt(dcmdt croc)₂], the T₁ values have been found to vary between 0.52 and 770 μs between 300K and 20K, respectively. The temperature dependence of the electron spin-lattice relaxation rate is about T³. Temperature-dependent T₁ values thus obtained have been interpreted in terms of both direct and Raman processes.