Space formations and nonlinear properties of noncentrosymmetric germanates

Abstract

Space formations of GeO polyhedra have been analyzed for 114 noncentrosymmetric germanates. The type of GeO polyhedra space formations is dependent on the stoichiometric ratio SR=n(O)/n(Ge), where n(O) is the number of oxygen and n(Ge) is the number of germanium atoms in formal composition of the compound. Individual (GeO) polyhedra are found for SR≥3 chains of the polyhedra that exist in the range of SR=3–5. Only framework formations are possible at SR≤2.7.