The understanding of the linear and nonlinear optical effects in the borate series crystals

Summary form only given. The investigations of band energy calculation method confirm that anionic group theory is successful for borate series crystals. In the case of refractive-index, birefringence in particular, the results are quite consistant with experiments. For calculating d/sub ii/ coefficients, the theory is basically successfull. Its major shortcoming is that it is unable to consider the effect of cations on the d/sub ii/ coefficients.