Structural transitions in hybrid improper ferroelectric Ca${}_3$Ti${}_2$O${}_7$ tuned by site-selective iso-valent substitutions: a first-principles study

C. F. Li, S. H. Zheng, H. W. Wang +8

Ca${}_3$Ti${}_2$O${}_7$ is an experimentally confirmed hybrid improper ferroelectric material, in which the electric polarization is induced by a combination of the coherent TiO${}_6$ octa…