Answers are grounded in this paper and cite their sources.
An improved method of calculating series limits T ∞ is presented: this consists in varying simultaneously T ∞ and the coefficients in the energy expansion of the quantum defect so as to obtain a least-squares fit to observed series term values. Analysis of the 1 D, 3 D and 3 F series of helium using this method gives T ∞ = 198 310 74±0 02 cm -1 , compared with 198 310 82±0.05 cm -1 obtained by Herzberg in 1958, the quoted error estimates being standard deviations in fitting procedures. An independent estimate of 198 310.77±0 02 cm -1 is obtained for the 3 F series using a polarization formula. The best estimate of T ∞ for helium is considered to be 198 310.75 cm -1 , with the error in fitting procedures unlikely to exceed ±0.02 cm -1 .
No takes yet. Share an insight, caveat, or question.
M. J. Seaton (1966) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: