Ionic polarizabilities in crystals at high pressures

The pressure dependence of ionic polarizabilities in alkali halides and flu orite-structured crystals has been evaluated via different methods and thei r results compared. Some methods had to be extended for the fluorite struct ure. Recent experimental data for cesium halides, together with that for al kali halides, allowed for a more complete analysis of results. When high pr essure data were available comparison allows for an evaluation of the valid ity of the methods themselves; these could then be applied to propose high pressure values for other crystals with measurements only at p = 0. (C) 200 1 Elsevier Science Ltd. All rights reserved.