{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"0e5c87ab14013302662136f230d68c41eaccc3f7f3230ab3c580b0f7f0235416","created":"2026-10-03T07:17:57Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"e0944512db58cfc3c3e3535d0d058629ff850ad9c3908febb84a07f25536677a","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"bio.electrolytes-confined.confined-water-dielectric","kind":"phenomenon","literature_status":"open","n":"1","parents":[],"plain":"Water squeezed into a gap about a nanometer wide barely responds to an electric field across the gap, as if it were oil, yet it responds enormously to a field along the gap. A single microscopic explanation of both facts is missing.","posed_since":"2018","precise":"For water in slits of height h between atomically flat graphite or hBN walls, the perpendicular dielectric constant falls to epsilon_perp ~ 2 for $h \\sim 1\\ \\mathrm{nm}$ (2018 measurement), while a 2025 measurement found the in-plane constant $\\epsilon_{\\mathrm{par}}$ of about 1000 at few-layer thickness with superionic-level conductivity. Determine whether a model of interfacial layers with an anisotropic local dielectric tensor reproduces both epsilon_perp(h) and epsilon_par(h), or whether nonlocal correlated polarization and proton transport are required. An answer is a first-principles or simulation prediction of epsilon_perp(h), epsilon_par(h) and conductivity that matches both data sets.","problem_ref":null,"references":"","settled_by":"Ab initio or validated force-field simulations of the measured geometries reproducing both dielectric components and the conductivity versus h, with the controlling molecular feature identified.","status_note":"The 2025 Nature in-plane measurement attributed the enhancement to disordered hydrogen bonding and fast proton exchange; the low out-of-plane value is broadly reproduced by simulations of interfacial ordering.","title":"Origin of the anisotropic dielectric response of nanoconfined water","topic_ref":"157a1ba9426f0d60e33212293f1b767b543732401ec3d0153c6ca684819a4974"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"cb641d1d3be27ceaa37615b62154bbb37f1fab1de43042d861f2c7cfa473243b","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"3102d64d11ad57721e1cd6269ef319d2791778bcde3384aedf035d37f76c2a8c","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"VYzUCl0iBPsRdPd0VL6LB3OPXYOoPo2_lTCLB0e7zQc39Y2lB0MmTa2Bhq3-wXHUSf5ayPE5L3gsb4NtJMvrCQ"},"schema":"pubphys.envelope/1"},"record_hash":"cb641d1d3be27ceaa37615b62154bbb37f1fab1de43042d861f2c7cfa473243b","leaf_index":761}