Spectroscopic investigation of a series of sodium lanthanide decatungstates, Na7H2Ln(III)(W5O18)2·nH2O (Ln: LaYb): the contribution of 4fn electrons to bonding interaction among Ln(III) and polyoxotungstates

Abstract A series of sodium lanthanide decatungstates, Na 7 H 2 Ln(III)(W 5 O 18 ) 2 · n H 2 O (LnLaYb) was synthesized and characterized by spectroscopic analyses. The 183 W-NMR chemical shifts for the W adjacent to Ln(III) correlated well with the contact parameter in the lanthanide induced shifts, 〈 Sz 〉, which had been theorized by Golding. The FT-Raman stretching frequencies for the LnOW bonding also correlated with the theoretical magnetic moments induced from the 4f n electrons in the lanthanide ions in addition to the ionic radii of Ln(III). A direct contribution of the 4f n electrons to the bonding interaction among Ln(III) and the oxotungstates is suggested.