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Niobocene Alkyne Complexes: Synthesis and Characterization of Neutral and Cationic d2 Metal Alkyne Derivatives. X-ray Crystal Structure of [Nb(η5-C5H4SiMe3)2(η2(C,C)-HC⋮CPh)(CH2Ph)]

A. A. Martin, A. Otero, P. Gómez-Sal, 1997 .