FTP, name this phenomenon by which there is a slight difference in the energy of the 2s and 2p levels in hydrogen.
The experiment which first determined this result was carried out in the microwave region of the spectrum when UV radiation failed. Today it is observed using the technique of saturation spectroscopy, where tunable dye lasers are used to minimize the effect of Doppler broadening, a phenomenon especially prevalent in hydrogen atoms. In other elements, the effect of shielding makes the effect negligible, but in hydrogen its value can be calculated to a great deal of precision, and its agreement with theory is one of the greatest pieces of evidence for quantum electrodynamics. FTP, name this phenomenon by which there is a slight difference in the energy of the 2s and 2p levels in hydrogen.
The experiment which first determined this result was carried out in the microwave region of the spectrum when UV radiation failed.
Lamb shift