Abstract
In this paper we describe the recursion method applied to a parametrized tight-binding Hamiltonian for any cluster of silicon atoms. A new method of dealing with the dangling bonds at the surface of the cluster is described. We direct this new calculation to two types of defect (the soliton and its vacancy complex) associated with reconstructed partial dislocations and to those configurations, such as kink saddle points, which are transition states in dislocation motion. A new mechanism for partial dislocation motion is suggested in the light of our results.