AI 中文总结
利用虚拟同位素取代分子动力学模拟，在α-Li₂SO₄模型系统中研究阳离子平移与阴离子旋转动力学相互作用，通过改变锂和氧质量控制扩散率，发现二者存在双向耦合及锂扩散活化能与同位素质量的关系，证明阴阳离子动力学模式耦合。
AI 中文摘要
我们通过虚拟同位素取代分子动力学（VISMD）模拟，在模型系统α-Li₂SO₄上表征阳离子平移和阴离子旋转动力学之间的相互作用。通过分别改变锂和氧的质量，依次独立控制锂的平移扩散率和硫酸根的旋转扩散率，表明两种扩散率都与各组分质量呈现幂律关系。改变任一扩散率都会对另一个产生影响，即阴离子和阳离子扩散动力学之间存在双向耦合。从变温/变质量数据集中表明，锂扩散的表观活化能强烈依赖于同位素质量，随硫酸根动力学加速而降低，这为阳离子和阴离子动力学之间的模式耦合提供了明确证据。
英文摘要
We characterise the interplay between cation-translational and anion-rotational dynamics on the model system $\rm α\text{-}Li_{2}SO_{4}$ through virtual isotopic substitution molecular dynamics (VISMD) simulations. We independently control in turn the lithium translational- and sufate rotational- diffusivity by varying the masses of lithium and oxygen, respectively, showing that both diffusivities exhibit power-law relationships with the masses of each individual component. Changing either diffusivity produces an effect on the other; i.e. there exists a bidirectional coupling between anion and cation diffusive dynamics. From our variable-temperature/variable-mass dataset we demonstrate that the apparent activation energy for lithium diffusion depends strongly on the isotope mass, decreasing with accelerated sulfate dynamics; an observation which provides clear evidence of mode-coupling between cation and anion dynamics.
