This work reports the synthesis and spectral (infrared, Raman) characterization of the series of compounds (η5-C5H5)2LnBH4-THF, where Ln = Sm, Er, Yb. Vibrational spectra indicate that the mode of BH4· coordination is sensitive to the metal ionic radius. The Ln = Sm compound is proposed to have tridentate BH4- ligation, whereas the Ln = Yb compound is proposed to have bidentate ligation. The tetrahydrofuran can be removed for Ln = Yb and Er to yield complexes of the composition (η5-C5H5)2LnBH4. Vibrational spectra are similar to those of Be(BH4)2 and CH3Zn(BH4), suggesting a polymeric structure with bridging BH4- groups. All data suggest appreciable ionic character in the bonding of the tetrahydroborate ligand to the trivalent lanthanides.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry