Syntheses, Crystal Structure, and Second Harmonic Generation Response of Four Novel Noncentrosymmetric Tellurites of Quaternary A/M/Te/O (A = Ba, Sr, Ca; M = V, Nb, Ta) System: BaTaTeO, BaNbTeO, SrTaTeO, and CaVTeO.

Four new noncentrosymmetric tellurites of quaternary A/M/Te/O (A = Ba, Sr, Ca; M = V, Nb, Ta) system, namely, BaTaTeO (), BaNbTeO (), SrTaTeO (), and CaVTeO (), were synthesized and characterized by single-crystal X-ray diffraction, thermal analysis, diffuse reflectance spectroscopy, and powder second harmonic generation (SHG) response measurements. The isostructural compounds crystallize in the 222 space group and have a three-dimensional (TaTeO)/(NbTeO) anionic framework, whereas the layered compound crystallizes in the 2 space group and has a [VTeO] anionic layer. The phase-matching compounds , and and the non-phase-matching compound show powder SHG responses equivalent to ∼27, ∼13, ∼24, and ∼68% of that of LiNbO, respectively.