Magnetic Structure ofβ−CoSO4

Abstract

Recently the present authors reported the antiferromagnetic structure of CoS${\mathrm{O}}_{4}$, and a qualitative explanation was offered for the susceptibility and field-induced transition measurements of Borovik-Romanov and Kreines. It was assumed that the latter were made on the modification which is stable at ordinary temperatures. Subsequent study of a paper by Kreines, however, indicated that the single crystals used for these measurements were of the high-temperature modification (stable above 600\ifmmode^\circ\else\textdegree\fi{}C). The present paper describes the determination of the antiferromagnetic structure of this modification. There are four different (but symmetry related) spin directions in a magnetic cell of the same size as the chemical unit cell. The observed moment per ${\mathrm{Co}}^{2+}$ ion is found to be $(3.22\ifmmode\pm\else\textpm\fi{}0.32){\ensuremath{\mu}}_{B}$. While the structure accounts for the observation that none of the principal susceptibilities approaches zero at 0\ifmmode^\circ\else\textdegree\fi{}K, in other respects the structure is rather different from what one might expect from the magnetic measurements.