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This dataset compiles the results of our study of nuclear quantum effects (NQEs) and equilibrium isotope effects (EIEs) of 92 chemically diverse, organic molecular liquids. It contains the average macroscopic properties (density, molar volume, thermal expansion coefficient, isothermal compressibility, dielectric constant, heat of vaporization) and their associated standard errors computed with four independent classical and path-integral molecular dynamics (PIMD) simulations of each system and their deuterated counterparts. All simulations use the Topology Automated Force-Field Interactions (TAFFI) framework to describe the potential energy surface. In addition, the computed nuclear quantum effects and equilibrium isotope effects resulting from comparison of these simulations are included.
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Nuclear quantum effects in molecular liquids across chemical space
Abstract Nuclear quantum effects (NQEs) influence many physical and chemical phenomena, particularly those involving light atoms or occurring at low temperatures. However, their impact has been carefully quantified in few systems-like water-and is rarely considered more broadly. Here we use path-integral molecular dynamics to systematically investigate NQEs on thermophysical properties of 92 organic liquids at ambient conditions. Depending on chemical constitution, we find substantial impact across thermal expansivity, compressibility, dielectric constant, enthalpy of vaporization, and notably molar volume, which shows consistent, positive quantum-classical differences up to 5%; similar, less pronounced trends manifest as isotope effects from deuteration. Using data-driven analysis, we identify three features-molar mass, classical hydrogen density, and classical thermal expansivity-that accurately predict NQEs and facilitate understanding of how characteristics like branching and heteroatom content influence behavior. This work highlights the broad relevance of NQEs in molecular liquids, while also providing a conceptual and practical framework to anticipate their impact.
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- PAR ID:
- 10611798
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 16
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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