English

Isotope effects on the lattice parameter of cubic SiC

Materials Science 2015-05-13 v1

Abstract

Path-integral molecular dynamics simulations in the isothermal-isobaric (NPT) ensemble have been carried out to study the dependence of the lattice parameter of 3C-SiC upon isotope mass. This computational method allows a quantitative and nonperturbative study of such anharmonic effect. Atomic nuclei were treated as quantum particles interacting via a tight-binding-type potential. At 300 K, the difference Delta a between lattice parameters of 3C-SiC crystals with 12C and 13C amounts to 2.1 x 10^{-4} A. The effect due to Si isotopes is smaller, and amounts to 3.5 x 10^{-5} A when replacing 28Si by 29Si. Results of the PIMD simulations are interpreted in terms of a quasiharmonic approximation for the lattice vibrations.

Keywords

Cite

@article{arxiv.0907.2175,
  title  = {Isotope effects on the lattice parameter of cubic SiC},
  author = {Carlos P. Herrero and Rafael Ramirez and Manuel Cardona},
  journal= {arXiv preprint arXiv:0907.2175},
  year   = {2015}
}

Comments

4 pages, 3 figures