Competing polar and antipolar phases in n=2 Ruddlesden-Popper niobates and tantalates from first principles

This dataset contains the optimized structures from our density functional theory (DFT) calculations presented in our manuscript "Competing polar and antipolar phases in n=2 Ruddlesden-Popper niobates and tantalates from first principles" Input files for the calculations are also are provided.

Methods
This computational data was generated using the Vienna ab initio Simulation Package (VASP). This dataset contains optimized structures (in VASP format) for I4/mmm, I4mm, Fmm2, Amam (M5-), Acam, Amam (X3-), P4_2/mnm, A2_1am, Pnam for all four materials Li_2SrNb_2O_7,  Li_2CaNb_2O_7,  Li2SrTa2O7 and  Li_2CaTa_2O_7. Related metastable structural phases are also included along with the polar and antipolar structures of Li_2SrNb_2O_7. Intermediate structures accessed along energy barrier calculation generated by nudged elastic band (NEB) calculations also are included.