{"paper":{"title":"Ab initio calculation of electronic band structure of Cd$_{1-x}$Fe$_x$Se","license":"","headline":"The band gap of Cd1-xFexSe widens with increasing iron concentration and the antiferromagnetic phase is lower in energy.","cross_cats":["cond-mat.soft","physics.chem-ph"],"primary_cat":"cond-mat.mtrl-sci","authors_text":"Elshad Allahyarov, Matanat A. Mehrabova, Niyazi H. Hasanov, Nurana R. Gasimova","submitted_at":"2025-06-21T19:15:24Z","abstract_excerpt":"The purpose of this work was to calculate the electronic band structure of Cd$_{1-x}$Fe$_x$Se. Ab-initio, calculations are performed in the Atomistix Toolkit program within the Density Functional Theory and Local Spin Density Approximation on Tight Tiger basis. We have used Hubbard U potential $U_{Fe} = 2.42$eV for 3d states for Fe ions. Super-cells of 8 and 64 atoms were constructed. After the construction of Cd$_{1-x}$Fe$_x$Se ($x=$ 6.25%; 25%) super-cells, atom relaxation and optimization of the crystal structure were carried out. Electronic band structure,and density of states were calcula"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"The band gap for Cd1-xFexSe increases with Fe concentration: Eg=1.77 eV (FM) and 1.78 eV (AFM) at x=0.06, Eg=1.92 eV at x=0.25; antiferromagnetic phase is more stable.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The chosen Hubbard U value of 2.42 eV for Fe 3d states and the LSDA functional are assumed to be adequate for quantitative gap predictions in this alloy system.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"DFT+LSDA+U calculations on 8- and 64-atom supercells give band gaps of 1.77-1.78 eV at x=0.06 and 1.92 eV at x=0.25 for Cd1-xFexSe, with antiferromagnetic order lower in energy.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"The band gap of Cd1-xFexSe widens with increasing iron concentration and the antiferromagnetic phase is lower in energy.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"67d947c6c76d272545f71f5e494bc9ba33308426de14590968f79f1809ce3452"},"source":{"id":"2506.17794","kind":"arxiv","version":1},"verdict":{"id":"29e2409e-fb98-4a69-97ff-47941f314777","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T21:49:57.248412Z","strongest_claim":"The band gap for Cd1-xFexSe increases with Fe concentration: Eg=1.77 eV (FM) and 1.78 eV (AFM) at x=0.06, Eg=1.92 eV at x=0.25; antiferromagnetic phase is more stable.","one_line_summary":"DFT+LSDA+U calculations on 8- and 64-atom supercells give band gaps of 1.77-1.78 eV at x=0.06 and 1.92 eV at x=0.25 for Cd1-xFexSe, with antiferromagnetic order lower in energy.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The chosen Hubbard U value of 2.42 eV for Fe 3d states and the LSDA functional are assumed to be adequate for quantitative gap predictions in this alloy system.","pith_extraction_headline":"The band gap of Cd1-xFexSe widens with increasing iron concentration and the antiferromagnetic phase is lower in energy."},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":2,"snapshot_sha256":"e5ad36fb691e916b744fc07ec5268f9a8dc4d7e4b3ba4af1f67d7325b2bf5b9b"},"author_claims":{"count":1,"strong_count":1,"snapshot_sha256":"5e3b23b793a24ad44d50f012bed3c12f7c9e9c566d826ad85b79440943422c6c"},"builder_version":"pith-number-builder-2026-05-17-v1"}