We study the equilibrium geometries and growth modes of small stoichiometric (TiO)(n) (n less than or equal to 9) clusters by using the ab initio calculations within the framework of density-functional theory and the generalized gradient approximation. The resulting geometries show that the three-dimensional ring-like structures are more favorable energetically than the cubic-like structures and clusters of (TiO)(6) and (TiO)(9) have an unusual stability. Moreover, studies show that even larger clusters could be obtained by using (TiO)(2) and (TiO)(3) rings as the building blocks. (C) 2004 Elsevier B.V. All rights reserved.