Molecular field calculations of the phase diagram in PrCo2Si2

PrCo2Si2 has a collinear antiferromagnetic structure with a wave vector Q(1 ) = (0, 0, 1) for T < T-1 = 9 K, a high-order commensurate one with Q(2) = (0,0, 25/27) for T-1 less than or equal to T less than or equal to T-2 = 17 K and with Q(3) = (0, 0, 7/9) for T-2 less than or equal to T < T-N = 30 K . Molecular field calculations of the moment arrangements and magnetization processes of the compound were made with a molecular held model and the he ld-temperature magnetic phase diagram was reproduced. The magnetic transiti ons are discussed in connection with the wave-dependent molecular field coe fficients of the compound. (C) 2000 Elsevier Science B.V. All rights reserv ed.