Magnetization behavior of (NBu4)2Mn2[Cu(opba)]3 and related solvated ferromagnets

Direct current magnetization studies are reported for the organic ferromagnet (NBu4)2Mn2[Cu(opba)]3 (TC=22 K), where opba stands for o‐phenylenebis (oxamato), and related compounds obtained by solvating it with dimethylsulphoxide, methanol, and acetonitrile, which have TC values of 15, 12, and 14.5 K, respectively. M(H) plots for the first two compounds show very little width and criss‐cross at low applied field values (<50 Oe). Zero field‐cooled magnetization and field‐cooled magnetization curves for (NBu4)2Mn2[Cu(opba)]3 nearly overlap and its remanence plot changes sign at 11.5 K, exhibiting a compensation behavior. Negative remanent magnetization has also been observed for the other three compounds. The results are discussed in terms of the ferrimagnetic nature of the building blocks.