Table of Contents
ISRN Condensed Matter Physics
Volume 2013 (2013), Article ID 646042, 9 pages
http://dx.doi.org/10.1155/2013/646042
Research Article

Ab Initio Investigation of Nitride in Comparison with Carbide Phase of Superconducting InX (X = C, N)

Department of Physics, Rajshahi University, Rajshahi 6205, Bangladesh

Received 30 October 2012; Accepted 11 December 2012

Academic Editors: M. Durandurdu, A. Krimmel, and A. D. Zaikin

Copyright © 2013 M. Roknuzzaman and A. K. M. A. Islam. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The structural, elastic, electronic, thermal, and optical properties of superconducting nanolaminates Ti2InX (X = C, N) are investigated by density functional theory (DFT). The results obtained from the least studied nitride phase are discussed in comparison with those of carbide phase having value half as that of the former. The carbide phase is found to be brittle in nature, while the nitride phase is less brittle. Elastic anisotropy demonstrates that the c-axis is stiffer in Ti2InN than in Ti2InC. The band structure and density of states show that these phases are conductors, with contribution predominantly from the Ti 3d states. The bulk modulus, Debye temperature, specific heats, and thermal expansion coefficient are obtained as a function of temperature and pressure for the first time through the quasiharmonic Debye model with phononic effects. The estimated values of electron-phonon coupling constants imply that Ti2InC and Ti2InN are moderately coupled superconductors. The calculated thermal expansion coefficient is in fair agreement with the only available measured value for Ti2InC. Further the first time calculated optical functions reveal that the reflectivity is high in the IR-visible-UV region up to ~10 eV and 12.8 eV for Ti2InC and Ti2InN, respectively, showing these to be promising coating materials.