ISSN - 03759601, Physics Letters, Section A: General, Atomic and Solid State Physics, 1996, vol. 221, p. 370-374
Nature of the Darwin term and (Zα)4m3/M2 contribution to the Lamb shift for an arbitrary spin of the nucleus
The contact Darwin term is demonstrated to be of the same origin as the spin-orbit interaction. The (Zα)4m3/M2 correction to the Lamb shift, generated by the Darwin term, is found for an arbitrary nonvanishing spin of the nucleus, both half-integer and integer. There is also a contribution of the same nature to the nuclear quadrupole moment.