Data and post-processing scripts for Phys. Rev. B 99, 245127 -------------------------------------------------------------------- Mechanism and control parameters of the coupled structural and metal-insulator transition in nickelates -------------------------------------------------------------------- https://doi.org/10.1103/PhysRevB.99.245127 Oleg E. Peil, Alexander Hampel, Claude Ederer, and Antoine Georges The comressed tgz archive contains jupyter notebooks (https://jupyter.org/) that will read the data produced by VASP and the triqs DMFT framework (https://triqs.github.io/triqs/2.1.x/) and post-process it to the figures found in our publication. All input and relevant output data is contained in the archive: approximately 1.7GB uncompressed data files. The jupyter notebooks should explain the directory structure sufficiently and allow the reader to follow our post-processing workflows. The important output files for the DFT+DMFT calculations are called "observables_imp#.dat", which are read by the jupyter notebooks. To reproduce the calculations, all input files are included as well, where we used the dmft script included in the folder dmft_script and the corresponding input h5 archives can be found for each structure and material in the corresponding folder "h5-archives". Note: Due to license reasons we had to remove all VASP POTCAR files. Please have a look in the corresponding OUTCAR for information which POTCAR to use. notebooks: - bandwidth.ipynb: plot of the bandwidth across the nickelate series (Fig. 5) - dmft-rnio3-one-shot.ipynb: post-processing of DMFT calculation to produce Fig. 3 and Fig. 6 original abstract of the publication: Rare-earth nickelates exhibit a remarkable metal-insulator transition accompanied by a symmetry-lowering structural distortion. Using model considerations and first-principles calculations, we present a theory of this phase transition which reveals the key role of the coupling between electronic and lattice instabilities. We show that the transition is driven by the proximity to an instability towards electronic disproportionation which couples to a specific structural distortion mode, cooperatively driving the system into the insulating state. This allows us to identify two key control parameters of the transition: the susceptibility to electronic disproportionation and the stiffness of the lattice mode. We show that our findings can be rationalized in terms of a Landau theory involving two coupled order parameters, with general implications for transition-metal oxides.