Potential energy surface of AlW and W2 clusters has been studied by density functional theory. The results indicate that at a given spin multiplicity, usually more than one local minimum are found on the potential energy surface depending on the initial geometry. For AlW neutral cluster, global minimum is found at spin multiplicity 6, while for cation and anion species, spin multiplicities at 7 and 3 gives the global minimum, respectively. For W, cluster, global minimum is found at the lowest spin state, i.e., spin multiplicities 1, 2 and 2 for neutral, cation and anion species, respectively. (C) 2003 Elsevier Science B.V. All rights reserved.