Before presenting the results of the present study on the structural properties of TM-Hn complexes in Si, we describe the structure of the single substitutional TM impurity. Non-relativistic spin-polarised local density functional theory is used, within a pseudo-potential real-space method (AIMPRO) to study the structural properties of substitutional, neutral gold (Aus0) and single negatively charged platinum (Pt-s), as well as the TM-Hn complexes with n=1 and 2 for both impurities. Details on the method can be found elsewhere [#!aimpro!#].