Hyperfine anomaly in the spectrum of the osmium atom. Effect of the spatial distribution of nuclear charge

Contributions of the superposition of configurations ns(2) 5d(8) + ns5d(8)n 's (n = 1-5, n' = 6-10) and ns(2)5d(6) + ns5d(6)n's (n = 1-6, n' = 7-10) to parameters a(5d)(01), a(5d)(12), and a(5d)(10) of the hyperfine structure in the spectrum of the osmium atom Osl are calculated. It is shown that the nonzero contribution is made only to a(5d)(10). The effect of the spatial distribution of nuclear charge on the parameters of the hyperfine structure in the spectra of Os-187 and Os-189 isotopes and on the hyperfine anomaly for the 5d(7)6s levels in the spectrum of these isotopes is estimated. (C) 2001 MAIK "Nauka/Interperiodica".