Journal
JOURNAL OF PHYSICS-CONDENSED MATTER
Volume 24, Issue 3, Pages -Publisher
IOP PUBLISHING LTD
DOI: 10.1088/0953-8984/24/3/035401
Keywords
-
Categories
Funding
- Center for Theoretical and Applied Physical Sciences, Yarmouk University (Irbid, Jordan)
- Abdus Salam International Centre for Theoretical Physics (Trieste, Italy)
Ask authors/readers for more resources
The structural, vibrational and thermal properties of rocksalt ScN and YN are investigated by using a first-principles plane-wave approach. The results are discussed in comparison with the similarly calculated results for rocksalt MgO and zincblende AlN. The thermal expansivity (alpha(V)) computed within the quasi-harmonic approximation shows that there are significant anharmonic effects in ScN and YN, which are comparable to those in MgO. Since no experimental results are available for alpha(V) of either ScN or YN, the anharmonic effects are accounted for by a variant of the very recently introduced effective semiempirical ansatz (Phys. Rev. B 2009 79 104304) for calculating anharmonic free energy, which does not require any input from experiment. The validity of this very simple approach is demonstrated first by applying it to MgO. For the considered phase of AlN, the quasi-harmonic approximation is valid up to very high temperatures, and the thus obtained alpha(V) is in good agreement with experiment. The values of alpha(V) for semiconductor transition metal nitrides that crystallize in the rocksalt phase are higher than those for the zincblende phase of group-IIIB nitrides, and a major part of these differences is due to the crystal structure.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available