IMPURITY SOLUBILITY LIMITS IN IONIC-CRYSTALS, WITH APPLICATION TO CU2O

We have examined the possibility to dope, in particular Cu2O, with a s eries of aliovalent and isovalent ions. Detailed measurements were don e on Ag and Co doping. Other ions considered were: Li+, Na+, K+, Ni2+, Bi3+ and Wi+ (i = 4 or 6). The solubilities found were low, usually b elow similar to 0.1 cation% except for Ag+ which dissolved with 2 cati on%. An analysis is presented that allows calculating the solubility l imits. The concept of ''corresponding native defects'' of the host mat erial is introduced. With a knowledge of the concentration of the ''co rresponding native defects'', the standard chemical potential of the m aterials involved and the shear modulus of the host material, one can calculate the solubilities of the impurities.Using the results of that analysis to fit the experimental data the shear modulus of Cu2O is de termined to be 1.7 10(11) N/m(2), a value obtained from consideratio n of the strain on a microscopic, atomic scale.