A new technique for the construction of clusters in the search for global minima of atomic and molecular clusters is presented. The clusters are perturbed randomly according to a vibrational mode. In an application this technique is utilized in the search for global minima of water clusters described by the TIP4P potential. The well known basin-hopping is used as the search algorithm. New apparent global minima structures of clusters with 25-30 molecules are presented. The effectiveness of the new cluster generation mechanism allows an improved sampling of the potential energy surface at a low temperature parameter. (c) 2006 Elsevier B.V. All rights reserved.