BIS(ETA-CYCLOPENTADIENYL)-MOLYBDENUM AND -TUNGSTEN IMIDO COMPLEXES - X-RAY STRUCTURES OF [MO(ETA-C5H5)2(NBU(T))] AND [MO(ETA-C5H4ME)2(NBU(T))ME]I - Green, J; Green, M; James, J; Konidaris, P; Maunder, G; Mountford, P (1992)