F–K XANES Studies of Alkali Fluorides

F–K X-ray absorption near edge structures (XANES) of alkali fluorides, Lid, NaF, KF and RbF are measured by a photoelectric yield method. Na–K spectrum of NaF is also measured. The short-range order multiple scattering calculations for each K spectrum of LiF and NaF are performed. From comparison of the observed spectra with the calculated results, the effective cation charges are estimated with q =0.70±0.05 and 0.74±0.04 for LiF and NaF, respectively. These calculated F–K XANES spectra of alkali fluorides are not so sensitive to the charge distributions as cation K XANES. These results are in contrast with the case of alkaline-earth fluorides.