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arXiv · 1611.08453

Confinement effects on the nuclear spin isomer conversion of H$_2$O

Pierre-Alexandre Turgeon·Jonathan Vermette·Gil Alexandrowicz·Yoann Peperstraete·Laurent Philippe·Jean-Hugues Fillion·Xavier Michaut·Patrick Ayotte
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Abstract

The mechanism for interconversion between the nuclear spin isomers (NSI) of H$_2$O remains shrouded in uncertainties. The temperature dependence displayed by NSI interconversion rates for H$_2$O isolated in an Argon matrix provides evidence that confinement effects are responsible for the dramatic increase in their kinetics with respect to the gas phase, providing new pathways for o-H$_2$O $\leftrightarrow$ p-H$_2$O conversion in endohedral compounds. This reveals intramolecular aspects of the interconversion mechanism which may improve methodologies for the separation and storage of NSI en route to applications in nuclear magnetic resonance spectroscopy and imaging. It may also improve astronomers' ability to use their relative abundance in the interstellar medium as proxies, thereby providing a valuable "astronomical clock".

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Pierre-Alexandre Turgeon, Jonathan Vermette, Gil Alexandrowicz, Yoann Peperstraete, Laurent Philippe, Jean-Hugues Fillion, Xavier Michaut, Patrick Ayotte. 2017-02-16. Confinement effects on the nuclear spin isomer conversion of H$_2$O. https://doi.org/10.1021/acs.jpca.7b00893

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