Chaturvedi, VipulGhosh, SupriyaGautreau, DominiquePostiglione, William MDewey, John EQuarterman, PatrickBalakrishnan, Purnima PKirby, Brian JZhou, HuaCheng, HuikaiHuon, AmandaFitzsimmons, Michael RKorostynski, CarolineJacobson, AndrewFigari, LuccaBarriocanal, Javier GBirol, TuranMkhoyan, K AndreLeighton, Chris2022-11-092022-11-092022-11-09https://hdl.handle.net/11299/243023Enclosed in this dataset are all digital data from each main-text figure in the journal article "Room-Temperature Valence Transition in a Strain-Tuned Perovskite Oxide" [Nature Communications, journal volume, page # pending]. Data includes: synchrotron X-ray diffraction, high-angle annular dark field transmission electron microscopy and energy dispersive X-ray spectroscopy, electronic resistivity, SQUID magnetometry, polarized neutron reflectometry, scanning transmission electron microscope electron energy loss spectroscopy, density field theory calculations, and associated analysis of each. Data files are csv format, bundled by Figure number, and separated by panel letter. See Readme file for detailed descriptions of each data file.Cobalt oxides have long been understood to display intriguing phenomena known as spin-state crossovers, where the cobalt ion spin changes vs. temperature, pressure, etc. A very different situation was recently uncovered in praseodymium-containing cobalt oxides, where a first-order coupled spin-state/structural/metal-insulator transition occurs, driven by a remarkable praseodymium valence transition. Such valence transitions, particularly when triggering spin-state and metal-insulator transitions, offer highly appealing functionality, but have thus far been confined to cryogenic temperatures in bulk materials (e.g., 90 K in Pr1-xCaxCoO3). Here, we show that in thin films of the complex perovskite (Pr1-yYy)1-xCaxCoO3-delta, heteroepitaxial strain tuning enables stabilization of valence-driven spin-state/structural/metal-insulator transitions to at least 291 K, i.e., around room temperature. This dataset contains all digital data published in the Nature Communications paper of the same name.Creative Commons Attribution 4.0 International licensehttps://creativecommons.org/licenses/by/4.0/PYCCOCobaltitesStrain controlEpitaxyDatasethttps://doi.org/10.13020/7wff-1y61