Crystal growth, ionic conductivity, and photolysis of pure and impurity-doped lead bromide single crystals

Abstract

In this paper an account is given of the preparation of lead bromide single crystals undoped and doped with monovalent and trivalent cations and with oxygen.

The conductivity of these crystals has been measured in the temperature region 50–300°C. The thermal disorder appeared to be of the same Schottky type as in lead chloride. From the slopes of the conductivity curves the activation heat for the anion vacancy migration has been calculated to be 0.29 ± 0.04 eV and the heat required for the formation of one set of vacancies 1.4 ± 0.1 eV.

Irradiation of pure lead bromide with ultraviolet light gives a characteristic damaging as is made visible by electron and optical microscopy. The increase of the optical density varies as the square root of the irradiation time.