Influence of polyatomic impurity ions on the growth process of alkali iodide crytals

Abstract

It has been shown that by introduction of polyatomic impurity ions the combined bands of the oscillation absorption of which partially overlap the region of the Plank radiation one can strongly affect the heat transfer and crystallization conditions. When growing large crystals by the automated method of pulling on a seed with feeding by the melt a positive effect of doping with impurity is achieved at relatively small concentrations of impurity ions which do not change yet the main scintillation characteristics of CsI(Tl) and CsI(Na). A qualitative explanation of the observed effect by the results of measurements of the absorption coefficient at room temperature is given in the present paper