INVESTIGATION OF THE TEMPERATURE FIELD/COMPOSITION MAGNETIC PHASE-DIAGRAM OF MN1-XMGXPS3/

The magnetic behaviour of manganese thiophosphate, MnPS3, has been inv estigated with regard to applied field, temperature and dilution. Samp les used were Mn1-xMgxPS3 for x = 0, 0.05, 0.075 and 0.10. MnPS3 is a quasi-two-dimensional layered antiferromagnet with an out-of-plane Isi ng anisotropy, and therefore, undergoes a spinflop transition. By meas uring the spinflop field (H-sf) at a variety of temperatures, extrapol ation to 0 K gave a single value for H-sf. H-sf decreased from 38 kOe for the pure material to 27 kOe for Mn0.925Mg0.075PS3, although no flo p was found for x = 0.10. The Neel temperatures were found for the fou r compositions, and vary from 78 K in the pure material to 65 K for Mn 0.925Mg0.075PS3, with Mn0.9Mg0.1PS3 proving anomalous with a T-N of 70 K. These measurements add to the knowledge of the temperature/field/c omposition magnetic phase diagram for this material. (C) 1998 Elsevier Science B.V. All rights reserved.