{"paper":{"title":"Pressure induced phase transitions in PbTiO$_3$ - a query for the polarization rotation theory","license":"","headline":"","cross_cats":["cond-mat.other"],"primary_cat":"cond-mat.mtrl-sci","authors_text":"J. Frantti, R. M. Nieminen, Y. Fujioka","submitted_at":"2007-02-16T13:48:30Z","abstract_excerpt":"Our first-principles computations show that the ground state of PbTiO$_3$ under hydrostatic pressure transforms discontinuously from $P4mm$ to $R3c$ at 9 GPa. Spontaneous polarization decreases with increasing pressure so that the $R3c$ phase transforms to the centrosymmetric $R\\bar{3}c$ phase at around 30 GPa. The first-order phase transition between tetragonal and rhombohedral phase is exceptional since there is no evidence for a bridging phase. The essential feature of the $R3c$ and $R\\bar{3}c$ phases is that they allow the oxygen octahedron to increase its volume $V_B$ at the expense of cu"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"cond-mat/0702388","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/cond-mat/0702388/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}