Kurzydłowski D. Potential energy barrier for proton transfer in compressed benzoic acid.
RSC Adv 2022;
12:11436-11441. [PMID:
35425083 PMCID:
PMC9004587 DOI:
10.1039/d2ra01736a]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 04/06/2022] [Indexed: 11/21/2022] Open
Abstract
Benzoic acid (BA) is a model system for studying proton transfer (PT) reactions. The properties of solid BA subject to high pressure (exceeding 1 kbar = 0.1 GPa) are of particular interest due to the possibility of compression-tuning of the PT barrier. Here we present simulations aimed at evaluating the value of this barrier in solid BA in the 1 atm – 15 GPa pressure range. We find that pressure-induced shortening of O⋯O contacts within the BA dimers leads to a decrease in the PT barrier, and subsequent symmetrization of the hydrogen bond. However, this effect is obtained only after taking into account zero-point energy (ZPE) differences between BA tautomers and the transition state. The obtained results shed light on previous experiments on compressed benzoic acid, and indicate that a common scaling behavior with respect to the O⋯O distance might be applicable for hydrogen-bond symmetrization in both organic and inorganic systems.
Pressure-induced shortening of O⋯O contacts within the dimers of solid benzoic acid leads to a decrease in the PT barrier and subsequent symmetrization of the hydrogen bond (an effect obtained only after taking into account the ZPE correction).![]()
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