Computing the Nonlinear Vibrational Response of Liquids and Biomolecules

计算液体和生物分子的非线性振动响应

• 批准号: 0105623
• 负责人: Roger Loring
• 金额: --
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2006-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0105623&HistoricalAwards=false
• 关键词: Computing; Nonlinear; Vibrational; Response; Liquids

Roger Loring of Cornell University is supported by the Theoretical and Computational Chemistry Program to develop methods for modeling nonlinear infrared spectroscopy in liquids and biomolecules with an atomistic level of description. Experimental observables in two-pulse and three-pulse vibrational echo measurements will be computed using classical molecular dynamics simulations. The fundamental theoretical issue underpinning this research is determining the optimal use of classical mechanical molecular dynamics data for complex systems to calculate nominally quantum mechanical observables. Two closely coupled research directions will be pursued: (1) to establish rigorously the validity regime of classical mechanical echo calculations, by performing numerically exact classical and quantum calculations for the same model system, and (2) to perform classical echo calculations for liquid-state and biomolecular models, for which quantum treatment is not feasible. Calculations will focus on myoglobin-CO, for which experiments are now characterizing the nature and time scales of protein fluctuations. Computing vibrational echoes in myoglobin-CO will identify the specific protein dynamics sensed by the CO ligand, and will guide the application of these new laser laboratory techniques to other bimolecular systems.Molecular motions in liquid solvents and in the heterogeneous environments of proteins are an integral part of the dynamics of chemical reactions and biological processes. A new generation of spectroscopic techniques can probe these motions directly. This research will allow for a detailed molecular picture of these processes by interpreting these new measurements.

康奈尔大学的罗杰·洛林在理论和计算化学计划的支持下，开发了用原子级描述来模拟液体和生物分子中的非线性红外光谱的方法。在双脉冲和三脉冲振动回波测量中的实验观察量将使用经典的分子动力学模拟来计算。支持这项研究的基本理论问题是确定复杂系统的经典力学分子动力学数据的最佳使用，以计算名义上的量子力学可观测值。将寻求两个紧密耦合的研究方向：(1)严格建立经典机械回波计算的有效性机制，对同一模型系统进行精确的经典和量子计算，以及(2)对不能进行量子处理的液体和生物分子模型进行经典回波计算。计算将集中在肌红蛋白-CO上，实验现在正在描述蛋白质波动的性质和时间尺度。计算肌红蛋白-CO中的振动回波将识别CO配体感知的特定蛋白质动力学，并将指导这些新的激光实验室技术应用于其他双分子系统。分子在液体溶剂和蛋白质的非均相环境中的运动是化学反应和生物过程动力学的组成部分。新一代光谱技术可以直接探测这些运动。这项研究将通过解释这些新的测量结果，提供这些过程的详细分子图像。