Learning from Correlations:Rare-earth Nickelates Revisited
We conducted a statistical study of the correlations between local structural distortions and critical transition temperatures of the RNiO3 family of compounds (R=rare earth). We showed gaps in scientific understanding of the reported structures of these materials known to exhibit metal-insulator and magnetic transitions and explained the discrepancies with DFT calculations.
Significance and Impact
Our study resolves an earlier discrepancy about the role of Jahn-Teller distortions vs. octahedral breathing modes in controlling the spin ordering transition temperature. The procedure for utilizing correlation coefficient heat maps to identify areas of high uncertainty can be used to better screen high-throughput databases. Our work also suggests machine learning studies that assume similar chemical formulas will have small variance in crystal structures should be cautious in model construction.