First-Principles Assisted Prediction of the Nonlinear Optical Behavior of Mg3B7O13Cl Crystal

In order to explore new nonlinear optical (NLO) crystals with superior performance, it is greatly desirable to understand the intrinsic relationship between the microscopic structural features and macroscopic optical properties of crystals. In this paper, the electronic structures and optical properties of Mg3B7O13Cl (MBOC), which contains B7O13 functional building blocks, were investigated to understand the structure — optical property relationship by first-principles calculation. Our calculated results show that the large band gap and the moderate second-harmonic generation (SHG) coefficient of MBOC (8.43 eV and d32 = 0.41 pm/V) are comparable to those of KBe2BO3F2 (8.64 eV and d11 = 0.46 pm/V). The origin of the large band gap and the moderate SHG response of MBOC were explained by combining electronic structure analysis and the SHG density method.