TY - JOUR

T1 - Thermal conductivity of wurtzite and zinc blende cubic phases of BeO from ab initio calculations

AU - Malakkal, Linu

AU - Szpunar, Barbara

AU - Siripurapu, Ravi Kiran

AU - Zuniga, Juan Carlos

AU - Szpunar, Jerzy A.

N1 - Publisher Copyright:
© 2017 Elsevier Masson SAS

PY - 2017/3/1

Y1 - 2017/3/1

N2 - The structural, mechanical, thermal and thermodynamic properties of Beryllium oxide (BeO) in the zinc blende (ZB) and wurtzite (WZ) form have been calculated using the density functional theory (DFT) in the general gradient approximation (GGA). The ground state structural and elastic properties of wurtzite BeO (w-BeO) is calculated using the new GGA ultrasoft pseudopotentials for solids (pbesol); the simulated results have shown excellent agreement with the experiments. The thermodynamic properties are studied using quasi-harmonic approximation (QHA), and the predicted properties agree well for the WZ phase for which the experimental data are available, while for ZB phase it remains to be validated with future experiments. Both Boltzmann transport equation (BTE) and Slack model were used to calculate the lattice thermal conductivity of wurtzite BeO (w-BeO). Furthermore, the thermal conductivity along the crystallographic ‘a’ and ‘c’ axis of wurtzite BeO is investigated using BTE. Our calculation of w-BeO agrees well with the available experimental measurements. Apart from these studies on w-BeO, we have also compared the mechanical, structural and phonon dispersions of z-BeO with previously reported theoretical studies. Additionally we report the volume thermal expansion and the heat capacity at constant pressure of z-BeO for the first time and the bulk thermal conductivity of zinc blende BeO (z-BeO) using BTE.

AB - The structural, mechanical, thermal and thermodynamic properties of Beryllium oxide (BeO) in the zinc blende (ZB) and wurtzite (WZ) form have been calculated using the density functional theory (DFT) in the general gradient approximation (GGA). The ground state structural and elastic properties of wurtzite BeO (w-BeO) is calculated using the new GGA ultrasoft pseudopotentials for solids (pbesol); the simulated results have shown excellent agreement with the experiments. The thermodynamic properties are studied using quasi-harmonic approximation (QHA), and the predicted properties agree well for the WZ phase for which the experimental data are available, while for ZB phase it remains to be validated with future experiments. Both Boltzmann transport equation (BTE) and Slack model were used to calculate the lattice thermal conductivity of wurtzite BeO (w-BeO). Furthermore, the thermal conductivity along the crystallographic ‘a’ and ‘c’ axis of wurtzite BeO is investigated using BTE. Our calculation of w-BeO agrees well with the available experimental measurements. Apart from these studies on w-BeO, we have also compared the mechanical, structural and phonon dispersions of z-BeO with previously reported theoretical studies. Additionally we report the volume thermal expansion and the heat capacity at constant pressure of z-BeO for the first time and the bulk thermal conductivity of zinc blende BeO (z-BeO) using BTE.

UR - http://www.scopus.com/inward/record.url?scp=85012278037&partnerID=8YFLogxK

U2 - 10.1016/j.solidstatesciences.2017.01.005

DO - 10.1016/j.solidstatesciences.2017.01.005

M3 - Article

AN - SCOPUS:85012278037

SN - 1293-2558

VL - 65

SP - 79

EP - 87

JO - Solid State Sciences

JF - Solid State Sciences

ER -