Synthesis, Structure, and Chemistry of Niobium Cationic Ketenimine Complexes, [Nb(.eta.5-C5H4SiMe3)2(.eta.2-PhRCCNPh-C,N)(L)]+. Molecular Structure of [Nb(.eta.5-C5H4SiMe3)2(.eta.2-Ph2CCNPh-C,N)(CH3CN)][PF6] | Publicación