Stabilization of tetrameric metavanadate ion by tris(1,10-phenanthroline)cobalt(III): Synthesis, spectroscopic and X-ray structural study of [Co(phen)(3)](3)(V(4)O(12))(2)Cl·27H(2)O.

A new complex salt of composition [Co(phen)(3)](3)(V(4)O(12))(2)Cl·27H(2)O (phen = 1,10-phenanthroline and [V(4)O(12)](4-) = tetrameric dodecaoxotetravanadate ion) was synthesized by reacting appropriate salts in aqueous medium. The complex salt has been characterized by elemental analyses, thermogravimetric analysis (TGA), cyclic voltammetry (CV), FT-IR and UV/Vis spectroscopies, solubility product and conductance measurements. Single crystal X-ray structure determination revealed ionic structure consisting of three complex cations, [Co(phen)(3)](3+), two [V(4)O(12)](4-) anions, one chloride and twenty seven lattice waters. Detailed structural and spectroscopic analyses of [Co(phen)(3)](3)(V(4)O(12))(2)Cl·27H(2)O show that the large anion is stabilized by the large cationic metal complex as there is preferred shape compatibility that leads to a large number of lattice stabilizing non-covalent interactions.