BOND LENGTHS AROUND ISOVALENT IMPURITIES AND IN SEMICONDUCTOR SOLID-SOLUTIONS

Using a bond orbital model, we calculate the bond length and polarity of semiconductors, the symmetric relaxations around isovalent impuriti es in semiconductor-impurity systems, and the bond-length variations i n solid solutions A1-xBxC of semiconductor alloys. We find that small impurities have a large relaxation, but the variations in bond energy are smaller than those of large impurities. The results are compared w ith other theoretical and experimental results and are found to be in excellent agreement with experiments.