MOLECULAR-STRUCTURE OF TI8C12 AND RELATED COMPLEXES

Application of valence-bond theory leads to the assignment to the molecule Ti8C12 of a cubic structure, point group O(h)m3mBAR, with 8 Ti at the cube corners, +/-(x x x, x xBAR xBAR, arrow curving up and over to the left)) where x = 1.78 angstrom, and with 12 C in pairs in the cube faces, +/-(0 y z, arrow curving up and over to the left), 0 yBAR zBAR, arrow curving up and over to the left) where y = 1.78 angstrom and z = 0.71 angstrom. The Ti-C and C-C bonds have bond number 4/3, corresponding to resonance of single and double bonds in 2:1 ratio.