Tetranuclear [{Ni(HL3)}{W(CN)8}]2 square: a case of antiferromagnetic {NiIIWV} interactions.
A tetranuclear cyano-bridged [{Ni(HL3)}{W(CN)8}]2 compound in a square geometry was formed by self-assembling of {W(CN)8}3- and {NiL3}2+ (L3=pentadentate ligand). The structure of the compound has been established by single crystal X-ray diffraction. The coordination sphere of the Ni ions is severely distorted with the macrocyclic ligand adopting a facial coordination with only four linkages to the metal center. The N atom of the pendant aminopropyl arm of L3 is no longer coordinated to the metal center but has undergone protonation during the assembling process. Magnetic measurements have revealed an unexpected antiferromagnetic behavior (J=-9 cm(-1)), which has been explained using a microscopic many-body electronic model Hamiltonian, based on DFT results. The many-body model is used to fit both the chiMT versus T and the M versus H plots obtained from experiments.
Venkatakrishnan
Thengarai S
TS
Laboratoire de Chimie de Coordination du CNRS, Université Paul Sabatier, 205 route de Narbonne, 31077 Toulouse, France.
Desplanches
Cédric
C
Rajamani
Raghunathan
R
Guionneau
Philippe
P
Ducasse
Laurent
L
Ramasesha
S
S
Sutter
Jean-Pascal
JP