A new non-centrosymmetric Gd-based borate crystal Rb7SrGd2(B5O10)3: growth, structure, and nonlinear optical and magnetic properties.

A new non-centrosymmetric borate crystal, Rb7SrGd2(B5O10)3, has been successfully grown by spontaneous nucleation technique from Rb2O–B2O3–SrO self-flux system. It crystallizes in the trigonal system space group R32 with lattice parameters a = b = 13.4975(5) A, c = 15.3223(8) A, α = β = 90 °, γ = 120 °, and Α = 3. Its three dimensional framework is composed of isolated GdO6 and SrO6 octahedra, RbOn (n = 6 and 8) polyhedra, and [B5O10]5– clusters. Rb7SrGd2(B5O10)3 exhibits multifunctional properties, which has both moderate second harmonic generation (SHG) responses (0.5 × KDP) and the paramagnetic characteristic with μeff = 8.18 μB. Thermal stability, infrared spectrum, and UV-Vis-NIR diffuse reflectance spectrum were performed on the title compound. The electronic band structures and density of states were also investigated by the first-principles calculations.