Electronic structure and linear optical property of BaSi2N2O2 crystal

The electronic structure and linear optical property of BaSi2N2O2 (BSNO) have been calculated by density functional method with the local density approximation. A direct band gap of 5.17 eV at G is obtained for BSNO. The calculated total and partial densities of states indicate that the top valence band is mainly constructed from the N 2p and O 2p states, the low conduction band mostly originates from Ba 4d and Si 3p states. The calculated linear optical property of BSNO is in good agreement with the experimental measurement.

► A direct band gap of 5.17 eV at G is obtained for BSNO. ► The valence band is constructed from N 2p and O 2p states and the conduction band from Ba 4d and Si 3p states. ► The covalence of N–O bond is much strong in BSNO. ► The absorption edge of BSNO is located at about 240 nm.