一种潜在的新型非线性光学材料—氟硼酸铍

A New Type of Potential Nonlinear Optical Material—Beryllium Fluoride Borate

氟硼酸铍(Be2(BO3)F,简写为BBF),属单斜晶系,空间群为C2。该化合物含有BO3平面三角形基团。BeO3F四面体与BO3基团连接形成六元环,通过Be-F-Be将层与层之间交叉联结起来。理论计算表明其Eg=7.80eV,吸收边在150nm;有较大的双折射率,Δn=0.0915;倍频系数计算结果显示:d22=-0.0723pm/v,d16=-0.0172pm/v,d14=-0.00928pm/v,d23=0.0053pm/v。对合成得到的材料粉末样品进行XDR物相测试验证和热分析。粉末倍频测试表明该材料的倍频讯号强度为KDP的1/4左右。实验证明BBF可能是一种潜在的紫外、深紫外非线性光学材料。

Beryllium fluoride borate, Be2（BO3）F belonging to space group C2 is built up with BO3 planar triangle group and BeO3F tetrahedral group. Theoretical calculation has been performed using CASTEP package. The results showed that Eg = 7.80eV, which contributed to a very short cutoff close to that of KBBF, λcutoff = 150nm ;a high birefractive index, △n = 0.0915 ;and the SHG effect coefficients are：d22 = - 0. 0723pm/v,d16 =- 0. 0172pm/v, d14 = - 0. 00928pm/v, d23 = 0. 0053pm/v,It has been synthesized by high-temperature solid-state chemical reaction, and investigated by X-ray diffraction and DTA. The signal intensity of the powder second harmonic generation effect of BBF was one fourth as large as that of KDP. It is confirmed that BBF should be a potential nonlinear optical material for the UV and deep UV generation.