Inorganic Chemistry, Vol.35, No.7, 1915-1917, 1996
Magnetic-Properties of Cu-2(Oh)(3)(Alkanecarboxylate) Compounds - Drastic Modification with Extension of the Alkyl Chain
Magnetic properties of the layered materials Cu-2(OH)(3)(n-C(m)H2(m+1)COO) (m = 0, 1, 7, 8, and 9) have been examined. X-ray powder diffraction patterns indicate that the interlayer distance increases in the order of In. The interlayer distances of the m = 0 and 1 materials are shorter than the molecular heights of the intercalated carboxylates, respectively, while the distances of the m = 7-9 materials are nearly double those of the molecular heights of the corresponding carboxylates, indicating a bilayer structure in them. The temperature dependence of the paramagnetic susceptibilities of the m = 0 and 1 materials suggests an intralayer ferromagnetic interaction and an interlayer antiferromagnetic interaction. The metamagnetic behavior is supported by S-shape dependence of their magnetization curves. The temperature dependence of the paramagnetic susceptibilities of the m = 7-9 materials indicates an intralayer antiferromagnetic interaction, in opposition to those in the former two. Further, they show a divergence of the ac magnetic susceptibility at 22 K, indicating a ferromagnetic order. The magnetization curve is characterized by an immediate increase at lower fields, succeeded by a gradual increase without saturation at higher fields. The magnetic properties of the m = 7-9 materials are well understood in terms of the weak ferromagnetism. The change of the intralayer magnetic interaction could be caused by some structural change in the CuOH layer with the intercalation.
Keywords:ANION-EXCHANGE