强激发下纳米液滴中的相关物理过程研究

项目名称： 强激发下纳米液滴中的相关物理过程研究

项目编号： No.11464050

项目类型： 地区科学基金项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 孙偲能

作者单位： 云南大学

项目金额： 50万元

中文摘要： 我们运用含时域的密度泛函理论和分子动力学来研究水分子团，以及含有有机分子的水分子团在超快激光和高速碰撞下发生的物理过程。这些物理过程包括分子与光子的相互作用、碰撞对分子的激发、电子与原子间的能量传递、分子间的电子输运、分子的离解、非平衡态热力过程、能量在分子内自由度间的传递、能量在分子间的传递等等。超快激光和高速碰撞对纳米液滴的激发被用于从水溶液中快速检测生物大分子的实验,这些新的实验原理在生物化学、生物物理、制药、医疗设备等领域有广阔的应用前景。到目前为止,相关物理过程的作用机制还没有很好的被理解，由于没有有效的实验手段来研究这些问题，基于理论模型的计算便成为定量考虑这些物理过程的唯一有效手段。我们的工作可以解释相关实验中的物理过程作用机制，为实验和应用的改进与发展取得详实的理论依据和具有重要参考价值的数据。

中文关键词： 含时密度泛函理论；多光子电离；强激光场；极端条件；非平衡态

英文摘要： We employ time dependend density functional theory (TDDFT) coupled with molecular dynamics to study the excitation processes in nano-water droplets, which are induced by ultrafast laser pulses and collisions. These droplets contain organic molecules and are interested in new experimental setups. In recent years, new experimental techniques were developed to quickly detect and analyse bio-molecules solved in water, the water buffer containing bio-molecules are produced into nano-scale droplets flying in a liquid beam via electrospray technique. The micro-droplets are either irradiated by an ultrafast laser pulse, or accelerated and lead to a surface, during the laser excitation or impact excitation, the disolved bio-molecule can be isolated from water and remains intact. However, complex physical effects are involved in these experiments, such as photon-electron interaction, impact induced electronic excitation, molecular dissociation, inter molecular energy transfer, intra molecular energy transfer, charge transfer and nonequilibrium thermo-dynamics. These phenomena play important role in surviving the bio-molecules. In our study, we consider the electronic excitation and charge transfer using TDDFT, the inter- and intra molecular energie transfer will be considered using molecular dynamics, thus, we are able to reproduce the physical processes take place in the corresponding experiments and improve our understanding. These efforts may be helpful to optimize the exprimental setups, or introduce more applications.

英文关键词： TDDFT;multiphoton ionization;strong laser field;extrem conditions;nonequilibrium