| Revue: | Brazilian journal of physics |
| Base de datos: | PERIÓDICA |
| Número de sistema: | 000403519 |
| ISSN: | 0103-9733 |
| Autores: | Pietropaolo, Antonino1 Senesi, Roberto2 Andreani, Carla2 Mayers, Jerry3 |
| Instituciones: | 1Universita degli Studi di Milano-Bicocca, Dipartimento di Fisica "G. Occhialini", Milán, Lombardia. Italia 2Universita degli Studi di Roma "Tor Vergata", Dipartimento di Fisica, Roma, Lazio. Italia 3Science and Technology Facilities Council, ISIS Pulsed Neutron and Muon Source, Oxford, Oxfordshire. Reino Unido |
| Año: | 2009 |
| Periodo: | Jun |
| Volumen: | 39 |
| Número: | 2 |
| Paginación: | 318-321 |
| País: | Brasil |
| Idioma: | Inglés |
| Tipo de documento: | Artículo |
| Enfoque: | Analítico |
| Resumen en inglés | A strong temperature dependence of proton mean kinetic energy was observed for liquid water around the density maximum and for moderately supercooled water. Line shape analysis of proton momentum distribution, determined from deep inelastic neutron scattering measurements, shows that there are two proton kinetic energy maxima, one at the same temperature of the macroscopic density maximum at 277 K, and another one in the supercooled phase located around 270 K. The maximum at 277 K is a microscopic quantum counterpart of the macroscopic density maximum, where energetic balance giving rise to the local water structure is manifest in the temperature dependence of kinetic energy. The maximum in the supercooled phase, with higher kinetic energy with respect to stable phases, is associated to changes in the proton potential as the structure evolves with a large number of H-bond units providing both stronger effective proton localization, as well as proton quantum delocalization |
| Disciplinas: | Física y astronomía, Química |
| Palabras clave: | Teoría cinética y plasmas, Fisicoquímica y química teórica, Agua, Líquidos, Funciones de distribución |
| Keyword: | Physics and astronomy, Chemistry, Kinetic theory and plasma, Physical and theoretical chemistry, Water, Liquids, Distribution functions |
| Texte intégral: | Texto completo (Ver PDF) |
