水纳米水滴的蒸汽压力
Matías H Factorovich1, Valeria Molinero, Damián A Scherlis
1Departamento de Química Inorgánica, Analítica y Química Física/INQUIMAE, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria , Pab. II, Buenos Aires, C1428EHA Argentina.
Journal of the American Chemical Society
|March 4, 2014
概括
凯尔文方程准确地描述了水滴的蒸汽压力到1纳米. 宏观热力学和分子描述仅在小于40个粒子的集群中才有差异.
科学领域:
- 热力学是一种热力学.
- 物理化学 物理化学
- 纳米技术 纳米技术
背景情况:
- 经典热力学假定连续物质,但分子现实是不连续的.
- 凯尔文方程描述了蒸汽压力,对于纳米尺度现象至关重要.
- 在纳米尺度上验证凯尔文方程在实验和计算上具有挑战性.
研究的目的:
- 研究凯尔文方程对纳米水滴的适用性.
- 为了确定有限系统的热力学描述的最小长度尺度.
主要方法:
- 使用大规范选方法进行分子动力学模拟.
- 计算有限水系统的蒸汽压力.
主要成果:
- 凯尔文方程对于小于1纳米的水滴仍然有效.
- 密度不均性发生在与水滴大小相比的尺度上.
- 结构在纳秒时间尺度上保持同质.
结论:
- 热力学描述适用于比以前认为的更小的系统.
- 对于40颗或更少颗粒的集群,宏观和分子描述有所不同.
- 时间平均是调和纳米尺度上的热力学和分子观点的关键.
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