http://www.cnr.it/ontology/cnr/individuo/prodotto/ID181650

Excess of proton mean kinetic energy in supercooled water (Articolo in rivista)

Type

Label

Excess of proton mean kinetic energy in supercooled water (Articolo in rivista) (literal)

Anno

Alternative label

Pietropaolo, A; Senesi, R; Andreani, C; Botti, A; Ricci, M; Bruni, F (2008)
Excess of proton mean kinetic energy in supercooled water
in Physical review letters; American Physical Society (APS), College Pk (Stati Uniti d'America)
(literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori

Pagina inizio

Pagina fine

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume

Rivista

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#pagineTotali

Note

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni

Universita' degli Studi di Roma Tor Vergata e CNR-IPCF, Universita' di Roma Tre (literal)

Titolo

Abstract

We find, by means of a deep inelastic neutron scattering experiment, a significant excess of proton mean kinetic energy < E(k)> in supercooled water, compared with that measured in stable liquid and solid phases. The measured values of < E(k)> at moderate degrees of supercooling do not fit the predicted linear increase with temperature observed for the water stable phases. This anomalous behavior is confirmed by the shape of the measured momentum distribution, thus supporting a likely occurrence of ground-state quantum delocalization of a proton between the O atoms of two neighboring molecules. These results strongly suggest a transition from a single-well to a double-well potential felt by the delocalized proton, with a reduced first neighbor O-O distance, in the supercooled state, as compared to ambient condition. (literal)

Editore