Time-Resolved EUV-Probed Surface Chemistry

时间分辨 EUV 探测表面化学

• 批准号: 0206736
• 负责人: Margaret Murnane
• 金额: $ 39万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-15 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0206736&HistoricalAwards=false
• 关键词: Time; Resolved; EUV; Probed; Surface

Professor Margaret Murnane of the University of Colorado is funded by the Analytical and Surface Chemistry Program to study femtosecond dynamics of well-characterized adsorbate/surface systems using extreme ultraviolet (EUV) and x-ray radiation. New shorter wavelengths of light produced through high harmonic generation will be utilized to access adsorbate core levels. In particular, charge transfer dynamics will be studied when oxygen on single crystal platinum (111) is subjected to laser pulses five femtoseconds in length. Also, the oxidation of CO on this same crystal face is to be examined. The ability to measure dynamics of a surface reactant as it evolves between different equilibrium states by photoemission has been very restricted, because ultrafast x-ray sources with sufficient flux and short pulse duration have not been available until very recently. The femtosecond and picosecond timescales are appropriate to the basic atomic motions underlying surface reactions.The work will increase our understanding of charge transfer processes on surfaces. Charge transfer is a chemical phenomenon underlying diverse processes such as electrochemistry and biochemistry. The area of femtochemistry was recently recognized as a frontier by the Nobel Prize in Chemistry in 1999.

科罗拉多大学的Margaret Murnane教授由分析和表面化学计划资助，使用极紫外线（EUV）和X射线辐射研究表征良好的吸附物/表面系统的飞秒动力学。 通过高次谐波产生的新的较短波长的光将被用于访问吸附物核心水平。 特别是，当单晶铂（111）上的氧受到5飞秒长的激光脉冲时，将研究电荷转移动力学。 此外，要检查CO在该相同晶面上的氧化。 由于具有足够通量和短脉冲持续时间的超快X射线源直到最近才可用，因此通过光电发射测量表面反应物在不同平衡状态之间演变时的动力学的能力受到很大限制。 飞秒和皮秒时间尺度适合于表面反应中原子的基本运动，这一工作将增加我们对表面电荷转移过程的理解。 电荷转移是电化学和生物化学等多种过程的基础化学现象。 飞秒化学领域最近被1999年诺贝尔化学奖确认为前沿领域。