Theory of the ESR spectra of Tl2+ ions in K2SO4 single crystals

The electron paramagnetic resonance spectrum of β‐K2SO4: Tl2+ is considered. The cluster model of the paramagnetic centres is used. It is suggested that the spectrum anisotropy is caused by the crystalline electric field which mixes the state 2P of the Tl2+ ion to the ground state 2S. Such an electric field is absent in the point charge model. An additional proof of the important role of the overlap of the Tl2+ and oxygen ion electron orbits is obtained when analysing the hyperfine structure of the ESR spectrum. [Russian Text Ignored].