The elastic, electronic, and optical properties of BaGe2P2 and BaGe2As2: A first-principles study

• Published in: Physica. B, Condensed matter Condensed matter, 2023-02, Vol.650, p.414546, Article 414546
• Main Authors: Liu, Meng, Qin, Mengli, Sa, Rongjian, Liu, Diwen
• Format: Article
• Language: English
• Subjects: BaGe2X2; Band structure; DFT; Elastic constant; Optical properties
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2022.414546

In the current work, we have explored the structural, elastic, electronic, and optical properties of BaGe2P2 and BaGe2As2 in detail. The simulated structural parameters are consistent with the experimentally observed data. Both compounds are mechanically stable and brittle materials. Two compounds are indirect band gap semiconductors, and the band gap reduction is caused by the substitution of P by As. The calculated band gap of BaGe2P2 is suitable for optoelectronic applications. It is revealed for BaGe2P2 and BaGe2As2 that the top of the valence band is mainly dominated by the P-3p (or As-4p) and Ge-4p orbitals, while the bottom of the conduction band is contributed from the Ge-4s, Ba-5d, Ge-4p, and P-3p (or As-4p) orbitals. The analysis of optical properties shows that BaGe2P2 has strong optical absorption capacity in the visible region. This work can provide useful information for the experiment to explore the potential of BaGe2P2 in solar cells.