On the Neutron Diffraction Study of Cr₂As

Abstract

A powder neutron diffraction study has been made of Cr 2 As with the spectrometers at the NRX and NRU reactors of Atomic Energy of Canada Ltd. Published magnetic and thermal data show this substance to be an antiferromagnetic with a Néel temperature of 393°K. Antiferromagnetic order along the c axis has been established in the present study by the presence of the magnetic line \(\left(00\frac{1}{2}\right)\). The magnetic line (100) has been found to be present, which shows another type of antiferromagnetic order developed in the c -plane. None of the antiferromagnetic spin structures which were tried in order to explain the observed peak intensities has been completely successful, but the most favorable is that in which Cr( a ) moments couple antiferromagnetically within the c -plane.