Synthesis, crystal structure and optical properties of an indium phosphate K3In3P4O16

An alkali-metal indium phosphate crystal, K{sub 3}In{sub 3}P{sub 4}O{sub 16}, has been synthesized by a high-temperature solution reaction and exhibits a new structure in the family of the alkali-metal indium phosphates system. Single-crystal X-ray diffraction analysis shows the structure to be monoclinic with space group P2{sub 1}/n, and the following cell parameters: a=9.7003(18), b=9.8065(18), c=15.855(3) A, beta=90.346(3){sup o}, V=1508.2(5) A{sup 3}, Z=4, R=0.0254. It possesses three-dimensional [In{sub 3}(PO{sub 4}){sub 4}]{sub n}{sup 3-} anionic frameworks with tunnels occupied by K{sup +} cations running along the a-axis. The emission and absorption spectra of the compound have been investigated. Additionally, the calculations of energy band structure, density of states, dielectric constants and refractive indexes have been performed with the density functional theory method. Also, the two-photon absorption spectrum is simulated by two-band model. The obtained results tend to support the experimental data. - A new indium phosphate crystal, K{sub 3}In{sub 3}P{sub 4}O{sub 16}, was synthesized by a high-temperature solid-state reaction with space group P2{sub 1}/n. It possesses three-dimensional [In{sub 3}(PO{sub 4}){sub 4}]{sub n}{sup 3-} anionic frameworks built by InO{sub 6} octahedra, InO{sub 7} decahedra and PO{sub 4} tetrahedra, and with tunnels occupied by K1 and K2 running along the a-axis, while K3 cationsmore » are located in cavities of the structure.« less