Magnetic Structure ofβCoSO4

Abstract
Recently the present authors reported the antiferromagnetic structure of CoSO4, 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°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 Co2+ ion is found to be (3.22±0.32)μB. While the structure accounts for the observation that none of the principal susceptibilities approaches zero at 0°K, in other respects the structure is rather different from what one might expect from the magnetic measurements.