TY - JOUR
T1 - First-Principles Calculations of Thermodynamic Properties of Superhard Orthorhombic $\beta-BC_2N$
JO - Journal of Atomic and Molecular Sciences
VL - 3
SP - 243
EP - 252
PY - 2010
DA - 2010/01
SN - 1
DO - http://doi.org/10.4208/jams.012410.031810a
UR - https://global-sci.org/intro/article_detail/jams/8084.html
KW - density functional theory, thermodynamic properties, $BC_{2}N$.
AB - <p style="text-align: justify;">We investigate the thermodynamic properties of the potential superhard 
orthorhombic structure boron-carbonitride $\beta-BC_{2}N$ by using $ab$ 
$initio$ plane-wave pseudopotential density functional theory method within 
both local density approximation (LDA) and generalized gradient approximation 
(GGA). The lattice parameters ($a$, $b$ and $c$), equilibrium volume $V$, 
bulk modulus $B_{0}$ and its pressure derivative $B_{0}$&#39; have been calculated, 
and compared with those of diamond and cubic boron nitride (c-BN). The obtained 
results are in excellent agreement with the available experimental data and 
other theoretical results. Through the quasi-harmonic Debye model, we also 
investigate the thermodynamic properties of $\beta-BC_{2}N.$ The variation 
of the thermal expansion $\alpha$, the heat capacity $C_{V}$ and the Grüneisen 
parameter $\gamma$ with pressure $P$ and temperature $T$, as well as the 
pressure-normalized volume ($P$-$V_{n}$) and the pressure- bulk modulus ($P$-$B$) 
relationship of $\beta-BC_{2}N$ are obtained systematically.</p>