Na 11 Ta 8 P 7 O 43 : (Ta 8 O 33 ) bi-capped triangular prisms connected by PO 4 groups resulting in a phase-matched second harmonic response.

Much effort has been devoted to synthesizing nonlinear optical crystals with efficient second harmonic responses. Herein, a tantalum phosphate crystal NaTaPO with a moderate second harmonic response was obtained using self-fluxes of NaHPO and NaHPO. NaTaPO belongs to the c space group of monoclinic systems with cell parameters of = 8.5710(2) Å, = 15.1144(4) Å, = 28.7712(7) Å, = 92.304(2)°, = 4. Its structural features were unique (TaO) bi-capped triangular prisms uniformly oriented with a PO connection in the plane, which were further joined through additional PO groups in the direction, resulting in moderate nonlinear effects. In addition, this crystal has the characteristics of phase-matchable second harmonic generation, a shorter cutoff edge than the known materials LiTaO and KTiOPO, and high transmittance from the visible to the near infrared band, and may serve as a potential nonlinear optical crystal.