X-band (9.60 GHz) EPR measurements were carried out on a single-crystal of
Cr3+ -doped zinc maleate tetrahydrate at room, liquid-nitrogen, and liquid
helium temperatures for various orientations of the external magnetic field
in three mutually perpendicular planes. The values of the spin-Hamiltonian
parameters were estimated using a rigorous least-squares fitting procedure
. The absolute sign of the zero-field splitting parameter, b(2)(0) was dete
rmined to be negative from liquid-helium temperature data, and its value wa
s found to be unusually large (similar to 15 GHz). (C) 2000 Elsevier Scienc
e B.V. All rights reserved.