中国科学院特殊环境功能材料与器件重点试验室知识库

A new centrosymmetric alkaline-earth metal borate, Ba2B 10O17, has been successfully synthesized through high-temperature solid-state reactions. The single-crystal X-ray structural analysis shows that Ba2B10O17 crystallizes in the triclinic space group P1. The parameters of the triclinic unit cell are a = 6.7128(3) A˚, b = 9.8698(4) A˚, c = 9.9998(4) A˚, α = 76.860(3)°, β = 83.200(3)°, γ = 73.332(3)°, and Z = 2. The title compound features a [B10O17]∞ three-dimensional anionic framework with infinite channels in which the Ba ²⁺ cations are located. Ba2B10O17 possesses a large experimental band gap of 6.29 eV and a short cut-off edge lower than 180 nm proved by the transmission spectrum on a single crystal sample 0.5 mm in thickness. The calculated band structures and the density of states of Ba2B10O17 suggest that its indirect energy gap is 5.97 eV which agrees with the experimental result. The thermal behavior and the IR spectrum of Ba2B10O17 are also reported in this work.