Analysis of the absorption spectra of complex pentavalent actinide halides: LiUF6, agr;hyphen;NaUF6, and CsUF6

摘要

Absorption spectra of polycrystalline samples of LiUF6, agr;hyphen;NaUF6, and CsUF6have been recorded at 4, 77, and 298 K. This group of compounds has a common sixfold Undash;F coordination that approaches an octahedral site symmetry for LiUF6but exhibits increasing trigonal distortion (D3dsymmetry) along the indicated series. Spectra have been systematically interpreted as consisting of sequences of vibronic transitions coupled to wellhyphen;defined electronic excited states. Crystalhyphen;field calculations have been performed.