Interrelationship “Structure-Property” for the Crystals of Noncentrosymmetric Tungstates

A set of ∼100 noncentrosymmetric (NCS) tungstates has been observed in reference to nonlinear optical properties. It has been found that on the plane of the shortest oxide bond lengths the NCS tungstate crystals are positioned into three intersected ellipses of «acentricity». The non-monotonic dependence of nonlinear optical susceptibility χ(2) on the shortest chemical bond length L(W-O) obtained for tungstates shows two pronounced maximums at L(W-O) ∼173 and 187 pm. The suggested crystal chemistry analysis is useful for searching new noncentrosymmetric tungstate crystals.