SYNTHESIS AND MOLECULAR-STRUCTURE OF THE NOVEL TRIOSMIUM BIS(BENZENE)CLUSTER (CO)(6)(ETA(6)-C6H6)(MU(3)ETA(2)ETA(2)ETA(2)-C6H6]

The novel bis(benzene) complex (6)(mu(3):eta(2):eta(2):eta(2)-C6H6)(et a(6)-C6H6)] is prepared and characterised by single-crystal X-ray anal ysis; the cluster exhibits two distinct coordination modes of benzene, one terminally bound in an eta(6) manner, the other in a mu(3) face-c apping coordination mode.