{"paper":{"title":"Ab initio Derivation of Low-Energy Model for $\\kappa$-ET Type Organic Conductors","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cond-mat.str-el","authors_text":"Kazuma Nakamura, Masatoshi Imada, Ryotaro Arita, Taichi Kosugi, Yoshihide Yoshimoto","submitted_at":"2009-03-31T09:52:21Z","abstract_excerpt":"We derive effective Hubbard-type Hamiltonians of $\\kappa$-(ET)$_2X$, using an {\\em ab initio} downfolding technique, for the first time for organic conductors. They contain dispersions of the highest occupied Wannier-type molecular orbitals with the nearest neighbor transfer $t$$\\sim$0.067 eV for a metal $X$=Cu(NCS)$_2$ and 0.055 eV for a Mott insulator $X$=Cu$_2$(CN)$_3$, as well as screened Coulomb interactions. It shows unexpected differences from the conventional extended H\\\"uckel results, especially much stronger onsite interaction $U$$\\sim$0.8 eV ($U/t$$\\sim$12-15) than the H\\\"uckel esti"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0903.5409","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":""},"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"}