Na2Te3Mo3O16:: A new molybdenum tellurite with second-harmonic generating and pyroelectric properties

The synthesis, structure, and characterization of a new noncentrosymmetric molybdenum tellurite, Na2Te3Mo3O16, are reported. Na2Te3Mo3O16 crystallizes in the noncentrosymmetric monoclinic space group 12 (No. 5, cell choice 3) with a = 7.3373(10) angstrom, b = 11.2668(16) angstrom, c = 8.2369(18) angstrom, and beta = 97.387(3)degrees. The material exhibits a quasi-one-dimensional crystal structure, with each chain consisting of edge-shared MoO6 octahedra that are connected by TeO3 and TeO4 polyhedra. The SHG efficiency of Na2Te3O3O16, using 1064 nm radiation, is approximately 500 x alpha-SiO2 and is phase-matchable (type 1). The strong SHG efficiency is maintained up to the melting temperature. The maximum polarization is 0.189 mu C/cm(2) at 25 kV/cm, and the pyroelectric coefficient (total effect), p, is -2.6 mu C/m(2) K.