Direct Measurement of Competing Quantum Effects on the Kinetic Energy of Heavy Water upon Melting
Even at room temperature, quantum mechanics plays a major role in determining the quantitative behaviour of light nuclei, changing significantly the values of physical properties such as the heat capacity. However, other observables appear to be only weakly affected by nuclear quantum effects (NQEs)...
| Asıl Yazarlar: | , , , , , |
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| Materyal Türü: | Journal article |
| Dil: | English |
| Baskı/Yayın Bilgisi: |
2013
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| _version_ | 1826280563279921152 |
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| author | Romanelli, G Ceriotti, M Manolopoulos, D Pantalei, C Senesi, R Andreani, C |
| author_facet | Romanelli, G Ceriotti, M Manolopoulos, D Pantalei, C Senesi, R Andreani, C |
| author_sort | Romanelli, G |
| collection | OXFORD |
| description | Even at room temperature, quantum mechanics plays a major role in determining the quantitative behaviour of light nuclei, changing significantly the values of physical properties such as the heat capacity. However, other observables appear to be only weakly affected by nuclear quantum effects (NQEs): for instance, the melting temperatures of light and heavy water differ by less than 4 K. Recent theoretical work has attributed this to a competition between intra and inter molecular NQEs, which can be separated by computing the anisotropy of the quantum kinetic energy tensor. The principal values of this tensor change in opposite directions when ice melts, leading to a very small net quantum mechanical effect on the melting point. This paper presents the first direct experimental observation of this phenomenon, achieved by measuring the deuterium momentum distributions n(p) in heavy water and ice using Deep Inelastic Neutron Scattering (DINS), and resolving their anisotropy. Results from the experiments, supplemented by a theoretical analysis, show that the anisotropy of the quantum kinetic energy tensor can also be captured for heavier atoms such as oxygen. |
| first_indexed | 2024-03-07T00:15:34Z |
| format | Journal article |
| id | oxford-uuid:7ab969f9-261a-429c-88cd-c0ed682b931c |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T00:15:34Z |
| publishDate | 2013 |
| record_format | dspace |
| spelling | oxford-uuid:7ab969f9-261a-429c-88cd-c0ed682b931c2022-03-26T20:45:54ZDirect Measurement of Competing Quantum Effects on the Kinetic Energy of Heavy Water upon MeltingJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:7ab969f9-261a-429c-88cd-c0ed682b931cEnglishSymplectic Elements at Oxford2013Romanelli, GCeriotti, MManolopoulos, DPantalei, CSenesi, RAndreani, CEven at room temperature, quantum mechanics plays a major role in determining the quantitative behaviour of light nuclei, changing significantly the values of physical properties such as the heat capacity. However, other observables appear to be only weakly affected by nuclear quantum effects (NQEs): for instance, the melting temperatures of light and heavy water differ by less than 4 K. Recent theoretical work has attributed this to a competition between intra and inter molecular NQEs, which can be separated by computing the anisotropy of the quantum kinetic energy tensor. The principal values of this tensor change in opposite directions when ice melts, leading to a very small net quantum mechanical effect on the melting point. This paper presents the first direct experimental observation of this phenomenon, achieved by measuring the deuterium momentum distributions n(p) in heavy water and ice using Deep Inelastic Neutron Scattering (DINS), and resolving their anisotropy. Results from the experiments, supplemented by a theoretical analysis, show that the anisotropy of the quantum kinetic energy tensor can also be captured for heavier atoms such as oxygen. |
| spellingShingle | Romanelli, G Ceriotti, M Manolopoulos, D Pantalei, C Senesi, R Andreani, C Direct Measurement of Competing Quantum Effects on the Kinetic Energy of Heavy Water upon Melting |
| title | Direct Measurement of Competing Quantum Effects on the Kinetic Energy of
Heavy Water upon Melting |
| title_full | Direct Measurement of Competing Quantum Effects on the Kinetic Energy of
Heavy Water upon Melting |
| title_fullStr | Direct Measurement of Competing Quantum Effects on the Kinetic Energy of
Heavy Water upon Melting |
| title_full_unstemmed | Direct Measurement of Competing Quantum Effects on the Kinetic Energy of
Heavy Water upon Melting |
| title_short | Direct Measurement of Competing Quantum Effects on the Kinetic Energy of
Heavy Water upon Melting |
| title_sort | direct measurement of competing quantum effects on the kinetic energy of heavy water upon melting |
| work_keys_str_mv | AT romanellig directmeasurementofcompetingquantumeffectsonthekineticenergyofheavywateruponmelting AT ceriottim directmeasurementofcompetingquantumeffectsonthekineticenergyofheavywateruponmelting AT manolopoulosd directmeasurementofcompetingquantumeffectsonthekineticenergyofheavywateruponmelting AT pantaleic directmeasurementofcompetingquantumeffectsonthekineticenergyofheavywateruponmelting AT senesir directmeasurementofcompetingquantumeffectsonthekineticenergyofheavywateruponmelting AT andreanic directmeasurementofcompetingquantumeffectsonthekineticenergyofheavywateruponmelting |