Stability, elastic and electronic properties of palladium nitride

• Published in: Journal of physics. Condensed matter Vol. 22; no. 1; pp. 015404 - 015404 (6)
• Main Authors: Chen, W, Tse, J S, Jiang, J Z
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 13.01.2010; Institute of Physics
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Elasticity, elastic constants; Electron density of states and band structure of crystalline solids; Electron states; Exact sciences and technology; Inorganic compounds; Mechanical and acoustical properties of condensed matter; Mechanical properties of solids; Other inorganic compounds; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Palladium nitride; Band structure; Elastic constants; Pressure effects; Semiconductor materials; Thermodynamic stability; Phonon density of states; Electronic density of states; High pressure; Phonon dispersion; Density functional method; Polymorphism; Crystal structure
• ISSN: 0953-8984; 1361-648X
• DOI: 10.1088/0953-8984/22/1/015404

The crystal structure, stability, elastic constants and electronic properties of PdN(2) for four polymorph structures: pyrite, marcasite, CoSb(2) and ST(AA), have been investigated using first-principles calculations. At zero pressure all four polymorphs are metallic and thermodynamically unstable but mechanically stable. Pyrite PdN(2) is found to be the lowest energy phase. It is metallic at ambient pressure but becomes a semiconductor at pressures higher than 18 GPa. The calculated phonon band structures of pyrite PdN(2) show the structure is dynamically stable up to 60 GPa. Good agreement between calculated and observed Raman frequencies was found, indicating that the recently synthesized palladium nitride at high pressure is likely to have a pyrite structure.