异形纳米粒子的自发定向运动
Spontaneous Directional Motion of Shaped Nanoparticle
摘要：
在纳米尺度空间和皮秒到纳秒中，发生了巨大的物理、化学和生物过程，而所涉及的颗粒/分子在热波动下的运动通常使用基于足够长的时间平均和球形颗粒形状的假设的扩散布朗运动的传统理论来分析。在这里，使用分子动力学模拟，我们表明，不对称形状的纳米粒子在稀溶液中具有自发定向运动的质心在有限的时间间隔内。这种意想不到的方向运动的驱动力在于它们的组成原子在扩散布朗运动开始之前的时间尺度上的取向调节期间所经历的相互作用的不平衡。推导出了描述这种定向运动的平均位移和方差的理论公式。我们的研究可能朝着建立一个完整的理论框架来描述从弹道到扩散制度的所有时间尺度上的各种形状的粒子在溶液中的运动迈出了重要的一步。
英文摘要：
In nanoscale space and pico- to nanoseconds enormous physical, chemical and biological processes take place, while the motions of involved particles/molecules under thermal fluctuations are usually analyzed using the conventional theory of diffusive Brownian motion based on both sufficiently long time averaging and assumptions of spherical particle shapes. Here, using molecular dynamics simulations, we show that asymmetrically shaped nanoparticles in dilute solutions possess spontaneous directional motion of the center of mass within a finite time interval. The driving force for this unexpected directional motion lies in the imbalance of the interactions experienced by their constituent atoms during the orientation regulation at timescales before the onset of diffusive Brownian motion. Theoretical formulae have been derived to describe the mean displacement and the variance of this directional motion. Our study potentially takes an important step towards establishing a complete theoretical framework for describing the motions of variously-shaped particles in solutions over all timescales from ballistic to diffusive regime.
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。
