Phenomenological modeling and design of new acentric crystals for optoelectronics

The sets of ∼600 noncentrosymmetric simple and binary oxides and ∼270 sulfides have been observed and classified. The fields have been defined on the plane of the shortest chemical bond lengths between cations and anions in which appearance of the crystals not having center of inversion is possible. Interrelation between nonlinear optical susceptibility χ(2) and chemical bonding in oxides and sulfides has been considered. The intervals of the shortest bond lengths cation–anion optimal for high rank χ(2) have been estimated for the compounds.