spectroscopic and computational studies of intermolecular interactions

分子间相互作用的光谱和计算研究

• 批准号: 364522-2008
• 负责人: Jäeger, Wolfgang
• 金额: $ 2.91万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Accelerator Supplements
• 财政年份: 2009
• 资助国家: 加拿大
• 起止时间: 2009-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=434289
• 关键词: spectroscopic; computational; studies; intermolecular; interactions

Intermolecular interactions are of importance in many areas, including processes such as condensation and evaporation, properties of condensed phase matter, biological processes such as protein folding and molecular recognition, and self assembly. This proposal describes study of intermolecular interactions by the characterization of molecular aggregates, from small complexes that contain a few molecules to large nano-clusters that consist of several thousand atoms, using state-of-the-art high resolution spectroscopic techniques. The two major innovative thrusts are: a) to use cluster spectroscopy to study paraHydrogen clusters doped with a probe molecule and b) to apply helium nanodroplet spectroscopy to the study chemical reactions on the microscopic level. Rotational spectroscopy of paraHydrogen molecules containing clusters will be facilitated by the construction of a chirped pulse broadband Fourier transform microwave spectrometer. The resulting spectroscopic parameters will be analyzed to detect, and to follow the evolution of, a bulk property, namely superfluidity, from the molecular, microscopic regime. These studies will be complemented by high level ab initio calculations of He - molecule and H2 - molecule dimers and subsequent bound state calculations. The theoretical results on the dimers will provide an important starting point for the experimental investigations of the larger clusters. We will use our newly constructed helium nanodroplet spectrometer to investigate photo-induced chemical reaction of species embedded in helium droplets that contain several thousand helium atoms. The helium nanodroplets serve here as microscopic reactor and calorimeter. Further spectroscopic studies on doped helium nanodroplets in the infrared, Terahertz, and microwave regions will contribute to our understanding of the dopant - helium droplet interaction and also of the interesting properties of the helium droplets themselves.

分子间相互作用在许多领域都很重要，包括凝聚和蒸发等过程，凝聚相物质的性质，蛋白质折叠和分子识别等生物过程，以及自组装。这一建议描述了通过使用最先进的高分辨率光谱技术对分子聚集体进行表征来研究分子间相互作用，从包含几个分子的小复合体到由数千个原子组成的大纳米团簇。两大创新是：a)利用原子簇光谱研究掺入探针分子的仲氢团簇；b)将氦纳米液滴光谱应用于微观水平上的化学反应研究。通过构建啁啾脉冲宽带傅里叶变换微波光谱仪，将促进含簇合物的对氢分子的旋转光谱。由此产生的光谱参数将被分析，以检测并跟踪来自分子微观区域的整体性质，即超流性的演变。这些研究将得到氦分子和氢分子二聚体的高水平从头计算以及随后的束缚态计算的补充。关于二聚体的理论结果将为更大团簇的实验研究提供一个重要的起点。我们将使用我们新建造的氦纳米液滴光谱仪来研究嵌入在包含数千个氦原子的氦液滴中的物种的光诱导化学反应。氦纳米液滴在这里用作微型反应器和热量计。对红外、太赫兹和微波波段的掺杂氦纳米液滴进行进一步的光谱研究，将有助于我们理解掺杂剂-氦液滴的相互作用，以及氦液滴本身的有趣性质。