Direct determination of the single-ion anisotropy in a one-dimensional magnetic system by high-field EPR spectroscopy; Synthesis, EPR, and X-ray structure of NixZn1-x(C2O4)(dmiz)(2) [x=0.07]

The synthesis, X-ray structure, and EPR measurements of the integer-spin linear-chain antiferromagnet [Ni(ox)(dmiz)(2)] (where ox = C2O42- and dmiz = 1,2-dimethylimidazole) are presented. The sign and size of the single-ion zero field splitting (Zfs) of the divalent Ni have been determined by high field/high-frequency EPR spectroscopy. The spectra of powder samples of the derivatives [NixZn1-x(C2O4)(dmiz)(2)] for x = 0.09 and 0.07, at frequencies ranging from 110 to 440 GHz allowed the accurate determination of the zfs parameters D and E, with D = 1.875(4) cm(-1) and E = 0.38 cm(-1). The X-ray structure has been determined from measurements on a single stal with x 0.07. Structural parameters are as follows: a = 14.5252(7) Angstrom