{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"b9626ebf86cb922c8d5a9a680df19adc3b66f8fa892ef6e6ee6e7bcb4df52fe9","created":"2026-10-03T07:17:57Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"2b720ad5aabd2439e669076f330274f9c7bf08a9266351dd78cb173778751a84","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"bio.nucleation.ice-homogeneous-rate","kind":"well-posed","literature_status":"partially-resolved","n":"1","parents":[],"plain":"Pure water droplets can stay liquid well below 0 C because ice needs a seed to start. How fast ice appears on its own at very low temperature, and which form of ice appears first, is still uncertain.","posed_since":"","precise":"Determine the homogeneous ice nucleation rate $J(T)$ in pure H2O between about 230 and 240 K, where measurements by different techniques disagree by several orders of magnitude and simulations (seeding with TIP4P/Ice and similar models) depend on CNT-based extrapolation. Decide whether CNT with a temperature-dependent ice-water interfacial free energy $\\gamma(T)$ reproduces $J(T)$, and confirm whether the critical nucleus is stacking-disordered ice.","problem_ref":null,"references":"","settled_by":"Mutually consistent measurements of J(T) by independent techniques and simulations with an accurate water model that reproduce them without fitted interfacial free energies.","status_note":"Seeding simulations reproduce measured rates within several orders of magnitude and indicate stacking-disordered critical nuclei; precise agreement is lacking (2026).","title":"Homogeneous ice nucleation rate of deeply supercooled water","topic_ref":"1380a85b09074fe5f36e74fddf9348a147e8d031ca52cae30320a53fa96359da"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"c3716a4f5f972ed80708ac02b371d4b64917b9bb898bae948e667dca97c0ccbe","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"5a1814d1c31143c4e14a752fb5e1b503b7b12bb075b45dd73e7181305e0c1a11","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"9we0ho8MIwZj3Qtl9oIdfbcK9OfEUvfOMHxol7gqB4HQ9_YbJC5sBTqFIaYa-GZ0MyX29s9kH-ew3ZgK9TYIBg"},"schema":"pubphys.envelope/1"},"record_hash":"c3716a4f5f972ed80708ac02b371d4b64917b9bb898bae948e667dca97c0ccbe","leaf_index":810}