Synthesis and magnetism of chromium(II) methylphosphonate, CrII(MePO3)·H2O: a new weak ferromagnet

Abstract

A new chromium(II) phosphonate, Cr^II(MePO₃)H₂O, is prepared and characterised; magnetic measurements in the temperature range 100–300 K show a typical Curie-Weiss behaviour with a Curie constant of 2.90(5) emu K mol^–1 and a negative Weiss constant θ of –226(6) K; the thermal variation of the magnetic susceptibility below 60 K depends upon the cooling mode (z.f.c. = zero-field cooled and f.c. = field cooled); the compound is a canted antiferromagnet with the ordering temperature T_N at 35.8(3) K.