Design, crystal structures, electronic structures and absorption spectra of MnSexTe1−xMoO6: A first principles exploration

The band gap values of MnSen/16Te1-n/16MoO6 (n = 1, 2, 3) are 2.650 eV, 2.733 eV and 2.497 eV, respectively. Compared with MnTeMoO6, the band gap values of these Se-doped structures increase, and MnSe0.125Te0.875MoO6 has the maximum value (increase about 9.8%). [Display omitted] •Se4+ would be an appropriate dopant to substitute for Te4+ in MnTeMoO6.•The structural stability would increase slightly in MnSexTe1−xMoO6.•The laser damage threshold would be improved in MnSexTe1−xMoO6. MnTeMoO6 is a nonlinear optical material with a potential application in mid-infrared nonlinear optics. But until now, its application is limited for several defects as poor mechanical and thermal performances. To improve the performance of MnTeMoO6, the Se-doping has been employed. MnSexTe1−xMoO6 has been designed, and calculated by using the first principles method. Crystal structures, electronic structures and absorption spectra of MnSen/16Te1−n/16MoO6 (n = 0, 1, 2, 3) have been investigated. The calculation results show that Se4+ ions have a great possibility to substitute Te-sites with equivalent isomorphism in MnTeMoO6. Fortunately, for the Se-doping ratio increase in MnSen/16Te1−n/16MoO6 (n = 1, 2, 3), the structural stability would increase slightly, the laser damage threshold would be improved. Meanwhile, the cleavage fracture of MnSexTe1−xMoO6 crystal would be affected by the c-axis lengthening. Unfortunately, the transmission of MnSexTe1−xMoO6 would become worse in the visible region, thus the laser frequency conversion efficiency would be affected. Taken together, to improve the performance of MnTeMoO6 crystal, Se4+ would be an appropriate dopant to substitute for Te4+. This research results will accelerate the application of MnTeMoO6 crystal, and have reference significance for the exploration and application of new functional materials.