CARBONYLCYANOMETALATES AS BUILDING BLOCKS: HETEROMETALLIC COMPLEXES CONTAINING Mn(mu-CN)M (M= Cu, Au, Pd or Pt), Mn(mu-CN)Pd (mu-dppm)2Mn and Mn(mu-CN)M-(mu-dppm)2Pd(mu-NC)Mn (M= Pt or Pd) CHAINS OF ATOMS AND CRYSTAL STRUCTURE OF THE MIXED-METAL CLUSTER [Ru3[(mu3-NC)MnCp(CO)2](mu-AuPPh3)(CO)10].