在薄弱和强烈无序的摩擦介质中量化能量格局
Ming-Gen Li1, Meng Hu2, Li-Ming Fan3
1Department of Physics, Shantou University, Shantou, Guangdong 515063, China.
The Journal of chemical physics
|January 8, 2024
概括
我们研究了随机摩擦如何影响复杂系统中的能量格局. 增加的摩擦粗度会影响扩散和键能量,这对生物和软物质动态至关重要.
科学领域:
- 统计力学 统计力学
- 物理化学 物理化学
- 生物物理学的生物物理.
背景情况:
- 复杂的系统经常表现出异质的环境,导致位置依赖摩擦.
- 了解能源格局的粗性是解释无序媒体中扩散和动态的关键.
- 一般化的Caldira-Leggett模型为研究具有随机摩擦的系统提供了一个框架.
研究的目的:
- 为了研究随机,位置依赖的摩擦对扩散系统的能量景观粗度的影响.
- 分析这种粗度如何影响扩散系数和分子相互作用,例如键解离.
- 运用这些发现来理解包括液态水和蛋白质在内的薄弱和强烈无序介质的动态.
主要方法:
- 在异质介质中扩散的系统中,使用通用的Caldira-Leggett模型建模随机摩擦.
- 分析一个高斯随机扩散度D(x) = kBT/α(x),以其平均值和对相关函数为特征.
- 将理论框架应用于液态水中的扩散运动和蛋白质折叠动态.
主要成果:
- 由于扩散性波动,重新规范化的内在扩散系数低于平均值.
- 诱导的弱内部摩擦增加了能源景观的粗度.
- 在液态水中,键解离能量接近实验值,波动参数增加.
- 对于蛋白质来说,能量格局从几到kcal/mol不等,而减少的逃逸率表明强烈的内部摩擦.
结论:
- 随机摩擦显著改变了能源景观的粗度,影响了系统动态.
- 该模型成功地解释了液态水和蛋白质折叠的现象,突出了研究结果的普遍性.
- 研究复杂系统中的能量景观对于理解生物,软和活性物质的动态至关重要.
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