μ-Phenoxo-μ-pseudohalide and μ-pseudohalide dinuclear, tetranuclear and one-dimensional complexes: magneto-structural correlation and interesting type of solid state isomerism

Five Schiff base ligands have been utilized to explore metallo-pseudohalide (azide or cyanate) systems. These ligands are the 1:1 condensation products of 3-methoxysalicylaldehyde with ethanolamine (H2L1)/1-(2-aminoethyl)-piperidine (HL2)/ 4-(2-aminoethyl)-morpholine (HL3) or salicylaldehyde with 1-(2-aminoethyl)-piperidine (HL4)/4-(2-aminoethyl)-morpholine (HL5). The derived complexes are as follows: Four heterobridged mu-phenoxo-mu(1,1)-azide/cyanate dinickel(II) compounds of composition [Ni(HL-N-3)]center dot 3H(2)O (1), [Ni(L-N-3)(N-3)(H2O)]center dot CH3CH2OH (2), [Ni(L (mu(1,1)-N-3)(CH3CN)(H2O)](ClO4)center dot H2O center dot CH3CN (3) and [Ni(HL-NCO)]center dot 2H(2)O (4); Two mu(1,3)-azide bridged tetranickel(II) compounds [{Ni-II(L-N-3)(H2O)}(4)] (5) and [{Ni-II(L-N-3)(H2O)}(4)] (6); Two mu(1,3)-azide/cyanate one-dimensional compounds [(CuL)-L-II-NCO)] (n) center dot 2nH(2)O (7) and [(CuL)-L-II-N-3)] (n) center dot 2nH(2)O (8). Except compound 5 which shows overall antiferromagnetic coupling, other compounds exhibit overall ferromagnetic interaction. Syntheses, crystal structures, magnetic properties, density functional theoretical (DFT) calculations and experimental/theoretical magneto-structural correlations have been carried out which have revealed some interesting observations on composition/topology, magneto-structural correlations and solid state isomerism. The results have been already published. The present report deals with a review of the salient and interesting features of these works.