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The main idea behind their design lies in (i) increasing the interlayer distance in the graphite-like domains, (ii) introducing the higher energy sites (e.g., point defects and n","work_id":"32114203-2acd-4e1d-99fd-d860672a454f","year":null},{"cited_arxiv_id":"","doi":"","is_internal_anchor":false,"ref_index":3,"title":"Results and Discussion While, from a theoretical perspective, AB graphite (space group: P6 3/mmc) is a thermodynamically stable form of carbon, in the context of C -based electrode materials one usual","work_id":"41e4dddd-bab2-4796-985f-20090703314b","year":null},{"cited_arxiv_id":"","doi":"","is_internal_anchor":false,"ref_index":4,"title":"Conclusions By combining DFT with cluster expansion across a range of interlayer spacings and AA/AB stackings, we transform the messy structural complexity of hard carbon and expanded graphite into a ","work_id":"b4008c42-6ccf-4307-81da-95c41a49038d","year":null},{"cited_arxiv_id":"","doi":"","is_internal_anchor":false,"ref_index":5,"title":"Methods All the density functional theory (DFT) calculations were done using the Vienna ab initio Simulation Package (VASP) version 6.2.1 [32–34], using the projector augmented wave (PAW) method [35].","work_id":"dd20a347-0f56-424f-bb15-eda159c0382a","year":2025}],"snapshot_sha256":"b146bef453f0b98fed195c83ed671f7b939740ae1363d3e2e0cbd3e76ec8d3a5"},"source":{"id":"2512.12422","kind":"arxiv","version":1},"verdict":{"created_at":"2026-05-16T22:27:22.913127Z","id":"6d4661e6-1ca9-4d8d-a141-1fa594d0f9a2","model_set":{"reader":"grok-4.3"},"one_line_summary":"DFT and cluster-expansion calculations identify 4.21 Å as the threshold above which Na intercalates readily in graphite-like carbon while Li capacity peaks narrowly near 3.75 Å with AA stacking preferred for both ions.","pipeline_version":"pith-pipeline@v0.9.0","pith_extraction_headline":"Na intercalation in carbon becomes thermodynamically stable above 4.21 Å spacing while Li capacity maximizes narrowly at 3.75 Å","strongest_claim":"Na intercalation becomes thermodynamically possible in large concentrations above 4.21 Å even without a change in interlayer spacing. 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