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High-precision calculations of the hyperfine constants for the low-lying excited 2S States of Be+
1Department of Chemistry, University of Wisconsin-Eau Claire, Eau Claire, Wisconsin 54702, USA.
Abstract:
High-precision Hylleraas-type calculations of the hyperfine constants for the four lowest excited 3 (2)S, 4 (2)S, 5 (2)S, and 6 (2)S states of the (9)Be(+) ion are reported. Small adjustments to the hyperfine constants arising from effects that include the finite nuclear mass, the magnetization density distribution over the nucleus, the Breit-Rosenthal correction for finite nuclear size, and lowest-order relativistic and quantum electrodynamic corrections are considered. The final values obtained for the hyperfine constants for the n (2)S states were: -158.78, -62.43, -30.66, and -17.29 MHz for n = 3, 4, 5, and 6, respectively.
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