Schoenfeld, W. G. ; Chang, E. S. ; Geller, M. ; Johansson, S. ; Nave, G. ; Sauval, A. J. ; Grevesse, N.

published in Astronomy and Astrophysics, 301, pp. 593 (1995)

Abstract: The quadrupole-polarization theory has been applied to the 3d^6^4s(^6^D)4f and 5g subconfigurations of Fe I by a parametric fit, and the fitted parameters are used to predict levels in the 6g and 6h subconfigurations. Using the predicted values, we have computed the 4f-6g and 5g-6h transition arrays and made identifications in the ATMOS infrared solar spectrum. The newly identified 6g and 6h levels, based on ATMOS wavenumbers, are combined with the 5g levels and found to agree with the theoretical values with a root mean-squared-deviation of 0.042cm^-1^. Our approach yields a polarizability of 28.07 a_o_^3^and a quadrupole moment of 0.4360+/-0.0010ea_o_^2^for Fe II, as well as an improved ionization potential of 63737.700+/-0.010cm^-1^ for Fe I.

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