硫酸铵中原子动力学的压力依赖性：II。振动
Pressure dependence of atomic dynamics in barocaloric ammonium sulfate: II. Vibrations
摘要：
硫酸铵是一种巨大的逆压热材料，价格便宜，可在商业上获得。开发其在冷却应用中的潜力需要了解驱动熵变化的机制。本文报道用非弹性中子散射和密度泛函理论研究在温度和压力条件下的声子。我们发现实验和计算结果之间的良好协议。对熵变起关键作用的铵离子解离模式可以通过它们的负格吕奈森参数来识别。我们的研究结果将相变中的结构差异与原子动力学中的结构差异联系起来，提出了设计新的热材料的途径。
英文摘要：
Ammonium sulfate is a giant inverse barocaloric material that is cheaply and commercially available. Exploiting its potential for cooling applications requires an understanding of the mechanism driving the entropy change. Here we report an investigation by inelastic neutron scattering and density functional theory of the phonons under working conditions of temperature and pressure. We find excellent agreement between the experimental and calculated results. The ammonium librational modes that are crucial to the entropy change are identifiable by their negative Grüneisen parameter. Our results connect the differences in structure across the phase transition to those in the atomic dynamics, suggesting a route towards designing new caloric materials.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
