Abstract
This contribution investigates structural and electronic properties as well as stability phase diagrams of surfaces of the cubic boron nitride (c-BN). Our calculated parameters for bulk c-BN agree reasonably well with both experimental and computed values available in the literature. Based on the energies of the three experimentally recognised phases of bulk boron, i.e. α-B36, β-B105 and γ-B28, we estimate enthalpy of formation of c-BN to be −2.8 eV. The c-BN(1 0 0) surface offers separate B and N terminations (denoted as c-BN(1 0 0)_B and c-BN(1 0 0)_N), whereas c-BN(1 1 1) and c-BN(1 1 0) are truncated with combinations of boron and nitrogen atoms (denoted as c-BN(1 1 1)_BN and c-BN(1 1 0)_BN). Optimised geometries of surfaces display interlayer displacements up to the three topmost layers. Downward displacement of surface boron atoms signifies a common geometric feature of all surfaces. Bulk c-BN and its most stable surface c-BN(1 0 0)_N possess no metallic character, with band gaps of 5.46 and 2.7 eV, respectively. We find that, only c-BN(1 0 0)_B configuration exhibits a metallic character. c-BN(1 1 0)_BN and c-BN(1 1 1)_BN surfaces display corresponding band gaps of 2.5 and 3.9 eV and, hence, afford no metallic property.
Original language | English |
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Pages (from-to) | 267-275 |
Number of pages | 9 |
Journal | Molecular Simulation |
Volume | 43 |
Issue number | 4 |
DOIs | |
Publication status | Published - Mar 4 2017 |
Externally published | Yes |
Keywords
- Cubic boron nitride
- DFT-QHA
- thermo-elastic properties
ASJC Scopus subject areas
- General Chemistry
- Information Systems
- Modelling and Simulation
- General Chemical Engineering
- General Materials Science
- Condensed Matter Physics