In the context of the search for environment-respectful, lead- and bismuth- free chemical compounds for devices such as actuators, SnTiO3 (ST) is investigated from first principles within DFT. Full geometry optimization provides a stable tetragonal structure relative to cubic one. From the equation of state the equilibrium volume of SnTiO3 is found smaller than ferroelectric PbTiO3 (PT) in agreement with a smaller Sn2+ radius. While ionic displacements exhibit similar trends between ST and PT a larger tetragonality (c/a ratio) for ST results in a larger polarization, PST = 1.1 C.m2. The analysis of the electronic band structure detailing the Sn-O and Ti-O interactions points to a differentiated chemical bonding and a reinforcement of the covalent bonding with respect to Pb homologue.
@article{arxiv.0807.2534,
title = {First principles studies of SnTiO3 perovskite as a potential ferroelectric material},
author = {S. F. Matar and M. A. Subramanian and I. Baraille},
journal= {arXiv preprint arXiv:0807.2534},
year = {2013}
}