New ferrocenyl phosphane ligands incorporating Si-P linkages, [(eta-C5H4SiMe2PR2)(2)Fe], where R= Ph and Me, and the corresponding metal complexes [Mo(CO)(4)(L)] have been prepared and characterised. The molecular structures of [(eta-C5H4SiMe2PR2)(2)Fe], where R =Ph and Me have been determined by single crystal X-ray diffraction. (C) 2003 Elsevier B.V. All rights reserved.