Ugur Baris E, Webb Michael A
Department of Chemical and Biological Engineering, Princeton University Princeton, Princeton, NJ, USA.
Nat Commun. 2025 Jul 1;16(1):5786. doi: 10.1038/s41467-025-60850-x.
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.
核量子效应（NQEs）影响许多物理和化学现象，尤其是那些涉及轻原子或在低温下发生的现象。然而，它们的影响仅在少数系统（如水）中得到了精确量化，很少被更广泛地考虑。在这里，我们使用路径积分分子动力学系统地研究了环境条件下92种有机液体热物理性质的核量子效应。根据化学组成，我们发现核量子效应在热膨胀系数、压缩系数、介电常数、汽化焓，尤其是摩尔体积方面有显著影响，摩尔体积显示出高达5%的一致的正量子-经典差异；类似的、不太明显的趋势表现为氘化引起的同位素效应。通过数据驱动分析，我们确定了三个特征——摩尔质量、经典氢密度和经典热膨胀系数——它们能够准确预测核量子效应，并有助于理解支化和杂原子含量等特征如何影响行为。这项工作突出了核量子效应在分子液体中的广泛相关性，同时也提供了一个概念和实用框架来预测它们的影响。
