The new d-f cyanido-bridged 1D assembly [Nd(pzam)(3)(H2O)Mo(CN)(8)]center dot H2O was prepared by self-assembly of pyrazine-2-carboxamide (pzam), Nd(NO3) center dot nH(2)O and (Bu3NH)(3)[Mo(CN)(8)] center dot 4H(2)O in acetonitrile. X-ray crystallographic studies indicate that the complex comprises chains of alternating, cyanido-bridged [Nd(pzam)(3)(H2O)](3+) and Mo(CN)(8)](3) fragments. The magneto-structural properties have been studied by field-dependent magnetization and specific heat measurements at low temperatures (>= 0.3 K). Below approximate to 10 K the Nd(III) moment is well approximated by an effective spin S = 1/2, with anisotropic g-tensor. The exchange coupling between the Nd(III) and the Mo(V) spins S = 1/2 along the structural chains is found to be ferromagnetic, with J/k(B) = 1.8 +/- 0.2 K and approximately XY (planar) anisotropy. No evidence for 3D interchain magnetic ordering is found. A comparison with magneto-structural data of other cyanido-bridged complexes involving the Nd(III) ion is presented. (c) 2008 Elsevier B.V. All rights reserved.
Crystal structure, magnetic and thermal properties of the one-dimensional complex [Nd(pzam)(3)(H2O)Mo(CN)(8)] center dot H2O
Evangelisti M;
2008
Abstract
The new d-f cyanido-bridged 1D assembly [Nd(pzam)(3)(H2O)Mo(CN)(8)]center dot H2O was prepared by self-assembly of pyrazine-2-carboxamide (pzam), Nd(NO3) center dot nH(2)O and (Bu3NH)(3)[Mo(CN)(8)] center dot 4H(2)O in acetonitrile. X-ray crystallographic studies indicate that the complex comprises chains of alternating, cyanido-bridged [Nd(pzam)(3)(H2O)](3+) and Mo(CN)(8)](3) fragments. The magneto-structural properties have been studied by field-dependent magnetization and specific heat measurements at low temperatures (>= 0.3 K). Below approximate to 10 K the Nd(III) moment is well approximated by an effective spin S = 1/2, with anisotropic g-tensor. The exchange coupling between the Nd(III) and the Mo(V) spins S = 1/2 along the structural chains is found to be ferromagnetic, with J/k(B) = 1.8 +/- 0.2 K and approximately XY (planar) anisotropy. No evidence for 3D interchain magnetic ordering is found. A comparison with magneto-structural data of other cyanido-bridged complexes involving the Nd(III) ion is presented. (c) 2008 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
