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Structural and thermodynamic properties of wurtzite-type aluminium nitride from first-principles calculations 下载免费PDF全文
The lattice parameter, bulk modulus and its pressure derivative of
the wurtzite-type aluminium nitride (w-AlN) are investigated by using
the Cambridge Serial Total Energy Package (CASTEP) program in the
framework of Density Functional Theory (DFT). The calculated results
are in good agreement
with the available experimental data and other theoretical results.
Through the quasi-harmonic Debye model, the dependences of the
normalized lattice parameters $a/a_{0}$ and $ c/c_{0}$, axial ratio
$c/a$, normalized primitive-cell volume $V/V_{0}$, Debye
temperature ${\it\Theta} _{\rm D} $ and heat capacity $C_{\rm V}$ on
pressure $P $ and temperature $ T$ are obtained. It is found that the
interlayer covalent interactions (Al-N bonds) are more (even a
little) sensitive to temperature and pressure than intralayer ones
(N--N bonds), which gives rise to a little lattice anisotropy in the
w-AlN. 相似文献
2.
The electronic and optical properties of the cubic zinc-blende (ZB)
structured filled tetrahedral semiconductor α-LiZnN
under pressure are investigated by using \textit{ab initio} plane
wave pseudopotential density functional theory method within the
generalized gradient approximation (GGA). The electronic band
structure and the density of state under pressure are systematically
described. The basic optical constants, including the reflection and
absorption spectra, the energy-loss function, the complex refractive
index and the dielectric function, are calculated and analysed at
different external pressures. Our results suggested that the ZB
α-LiZnN is transparent in the partially
ultra-violet to the visible light region, and it seems that the
transparency is hardly affected by the pressure. 相似文献
3.
This paper investigates the electronic structure and thermodynamic properties of LiBC in the hexagonal structure by using the generalized gradient approximation (GGA) and local density approximation correction scheme in the frame of density functional theory. The geometric structure of LiBC under zero pressure, and the dependences of the normalized lattice parameters a/ao and c/co, the ratio e/a, the normalized primitive volume V/Vo on pressure are given. The thermodynamic quantity (including the heat capacity Cv, Debye temperature 6~D, thermal expansion a and Grfineisen parameter -y) dependences on temperature and pressure are obtained through the GGA method and the quasi-harmonic Debye model. The band structures and density of state of LiBC under different pressures have also been analysed. 相似文献
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