Structure and lattice dynamics of the (001) surface of Sr2CuO2Cl2 have been studied by helium atom scattering (HAS). Analysis of diffraction patterns obtained by elastic HAS revealed a surface periodicity consistent with bulk termination, and confirms that the surface is non-polar and stable which favors a SrCl surface termination. Bulk and surface lattice dynamical calculations based on the shell-model were carried out to characterize the experimental phonon dispersions obtained by inelastic HAS. No experimental surface mode was observed above 200 cm−1. Comparison between the experimental data and theoretical results for two different slabs with SrCl and CuO2 terminations showed that the experimental data conforms exclusively with the SrCl surface modes.
@article{arxiv.cond-mat/0503680,
title = {Study of structure and lattice dynamics of the Sr$_2$CuO$_2$Cl$_2$(001) surface by helium-atom scattering},
author = {M. Farzaneh and XF. Liu and M. El-Batanouny and F. C. Chou},
journal= {arXiv preprint arXiv:cond-mat/0503680},
year = {2009}
}