Influence of a v c−Vacancy on Luminescence of Pb⁺ Centres in Alkali Halides

Luminescence of Pb⁺ centres in X‐irradiated Pb²⁺ doped KCl, KBr, and KI crystals is first observed at 1.29, 1.21, and 1.14 eV, respectively. It is excited in the bands of KCl:Pb²⁺ at 4.93, 4.45, 3.70, 2.03 eV, of KBr:Pb²⁺ at 5.20, 4.55, 4.20, 3.20, and at 5.10, 4.30, 3.91, 3.52, 3.02, eV for KI:Pb²⁺. The effect is studied of the presence of the cation vacancy on both, the excitation and emission spectra of the Pb⁺ centre. Temperature, kinetic, and polarization characteristics of Pb⁺ and Pb⁺v_c⁻‐centres in KCl:Pb²⁺ are investigated.