Estimation of Lamb-shift effects for molecules: Application to the rotation-vibration spectra of water - art. no. 024502

A simple approach is presented for approximating Lamb shifts, the leading q uantum electrodynamical (QED) effects, in molecules containing light elemen ts. The Lamb-shift contributions to the electronic energies are estimated f rom scaled nuclear and electronic Darwin terms. QED effects on the rovibrat ional states of water are found to be significantly larger than current exp erimental uncertainties, and only one order of magnitude smaller than curre nt computational uncertainties.