Electron Spin Resonance of Tl⁺⁺ Centres in KCl Crystals

Abstract

Abstract Thallium‐doped KCl crystals are X‐rayed at 77 °K. They are warmed up to 300 °K and then cooled down again to 77 °K. ESR signals showing a resolved hyperfine structure due to six chlorines are observed. These arise from a Tl ++ ion on a cation lattice site. The constants of the spin‐Hamiltonian are determined. Using Watanabe's theory [1] the coefficients of the ground state LCAO function are determined from the h.f.s. constants. From these data and from data of the optical absorption spectrum of Tl ++ [3] the g ‐shift is calculated and compared with the experimental value.