Is there any general rule for determine which element will make V.B and which will make C.B. For example if I want to know in TiO2 which element will make V.B and which will make C.B.
See the book "Solids and Surfaces A Chemist's View of Bonding in Extended Structures" by Roald Hoffmann, VCH Publishers, 1988. There, it is discussed how to obtain qualitatively the band structure and the density of states from the frontier orbitals of the atoms or monomers involved. Rutile TiO2 is explicitly discussed on p. 28ff.