Photodissociation Dynamics and Related Topics

光解离动力学及相关主题

• 批准号: 8813771
• 负责人: James Kinsey
• 金额: --
• 依托单位: William Marsh Rice University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-07-01 至 1989-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8813771&HistoricalAwards=false
• 关键词: Photodissociation; Dynamics; Related; Topics

Dr. Kinsey is supported by a grant from The Physicl Chemistry Program to perform research in the field of molecular dynamics. Dr. Kinsey has devised sophisticated spectroscopic measurement techniques which enable chemists to observe individual molecules in the process of photodissociation after they have absorbed a photon. The technique is being applied to photochemically important atmospheric compounds such as ozone and hydrocarbons. When a molecule absorbs photons of a wavelength that promote photodissociation, it usually falls apart in a time which is short compared to the characteristic time for emission of light. Thus only a very tiny fraction of the absorbed photons are re-emitted. The spectroscopic properties of this miniscule minority are, however, extraordinarily instructive in showing dynamic processes both in the electronically excited state and in the ground state. Unusually long progressions in ground-state vibrations appear. A time-dependent formulation of Raman scattering reveals that the pattern of intensities in these wide-ranging spectra relates directly to the excited-state potential energy surface. Dr. Kinsey's research centers on extension and refinement of this newly discovered approach to the dynamics of extremely short-lived molecules and stable ground states. The approach will combine experimental and theoretical efforts to shed light on the details of "half-collison" processes.

金赛博士得到了物理化学项目的资助，在分子动力学领域进行研究。金赛博士设计了复杂的光谱测量技术，使化学家能够在吸收光子后观察光解过程中的单个分子。这项技术正被应用于光化学上重要的大气化合物，如臭氧和碳氢化合物。当一个分子吸收了促进光解作用的波长的光子时，它通常在一段时间内分解，这段时间比发光的特征时间短。因此，只有很小一部分被吸收的光子被重新发射。然而，这一小部分的光谱特性在显示电子激发态和基态的动态过程方面具有非凡的指导意义。基态振动出现了异常长的进展。拉曼散射的时间依赖公式揭示了这些宽光谱中的强度模式与激发态势能表面直接相关。金赛博士的研究重点是扩展和改进这种新发现的方法，以研究极短寿命分子和稳定基态的动力学。该方法将结合实验和理论努力，揭示“半碰撞”过程的细节。