Theoretical studies of face centered cubic (FCC) Ti14C13+ and Ti13C13+ clusters: can met-cars form from these FCC structures?

The face centered cubic (FCC) Ti14C13+ structure was calculated by applying the intermediate neglect of differential overlap self-consistent field unrestricted Hartree-Fock method (INDO SCF UHF) after proper parametrization. The optimized Ti13C13+ structure, derived by removing a Ti atom from the corner of the FCC structure, is significantly more stable (by about 220 kcal/mol) than the one derived by removing a Ti atom from the middle of the face. This result implies that the Ti8C13+ met-car cannot form by photodissociation of six Ti atoms from the middle of the FCC faces. An alternative structure for the Ti14C13+ cluster is presented.