Thermochemistry of Metal-Ligand Bonds and the Dynamics of Collision-Induced Dissociation

金属-配体键的热化学和碰撞诱导解离的动力学

• 批准号: 0135517
• 负责人: Peter Armentrout
• 金额: $ 67.42万
• 依托单位: University of Utah
• 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: 2002-02-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0135517&HistoricalAwards=false
• 关键词: Thermochemistry; Metal; Ligand; Bonds; Dynamics

AbstractProposal: CHE-0135517PI: Armentrout, Peter B.This project consists of continuing research in the fields of chemical dynamics and gas-phase organometallic ion chemistry using a combined techniques of flow tube ion production and guided ion beam tandem mass spectrometry (GIBMS). With this apparatus, thermalized atomic and polyatomic ions will be produced. Detailed kinetic and thermodynamic data on single mass-selected species will be obtained by accurately measuring the absolute reaction probabilities at thermal and hyperthermal energies. Two new experimental facilities will be developed: 1) An electrospray ion (ESI) source that should enable more routine generation of nonvolatile and thermally fragile ions in the gas phase and provide easier access to multiply charged species. 2) A source to study state-specific chemistry of heavier transition elements that utilizes "electronic state chromatography". A range of chemical systems will be studied and will emphasize three related areas: 1) the dynamics of collision-induced dissociation; 2) the chemistry of the heavier third-row transition metals; and 3) metal ion binding to biologically relevant molecules. Implicit in all three areas will be theoretical calculations needed to augment the experiments. One motivation for this program is the obvious interest in making better correlations between the detailed information available from gas-phase ion studies with the "real world" of condensed-phase organometallic chemistry, homogeneous catalysis, and biological systems. We make the conscious choice to study simple systems that progress in complexity in order to quantitatively assess trends in metal chemistry. By comprehensively studying the thermochemistry of many metals and many ligands, the trends (periodic, changes with number of ligands, variations in electronic states) in the thermodynamic data allow us to transcend the gas-phase venue where the data are obtained. Students and post doctoral research associates will participate in this research.As chemical reagents, metals are important components of biological systems, acting as active sites in enzymes and helping to regulate cell function and to control structure. Technologically, metals are used extensively as catalysts to produce a wide range of important fine chemicals and fuels. In addition, molecules specifically designed to interact selectively with certain metals are needed for nuclear waste cleanup and decontamination. The research done in this project is designed to provide fundamental information about the strength of the interactions of metals with chemical components relevant to biological systems and the chemical industry. This is most readily accomplished by examining model systems that progress in complexity. This permits the trends in this information to be quantitatively assessed, which allows the development of predictive capabilities for more complex chemical environments. In this work, specialized devices known as guided ion beam tandem mass spectrometers are utilized to examine metal ion interactions with a variety of chemical species. This can be accomplished on single molecules such that interfering interactions from the environment can be eliminated. This allows the study to focus on elucidating the specific factors that control the interaction. A close collaboration with theory provides additional insight and provides essential predictive capabilities. The research will be done with students and post doctoral research associates who thereby receive training in preparation for advanced studies or entering the scientific/technical workforce.

摘要建议：CHE-0135517 PI：Armentrout，Peter B.该项目包括使用流管离子产生和引导离子束串联质谱（GIBMS）的组合技术在化学动力学和气相有机金属离子化学领域进行持续研究。用这种装置，将产生热化的原子和多原子离子。通过精确测量热能和超热能下的绝对反应概率，将获得关于单一质量选定物种的详细动力学和热力学数据。 将开发两个新的实验设施：1）电喷雾离子（ESI）源，它应该能够在气相中更常规地产生非挥发性和热脆性离子，并提供更容易获得多电荷物种。 2)一个利用“电子态色谱”研究重过渡元素特定态化学的来源。 将研究一系列化学系统，并将强调三个相关领域：1）碰撞诱导解离的动力学; 2）较重的第三排过渡金属的化学;和3）金属离子与生物相关分子的结合。 所有这三个领域都隐含着理论计算，以加强实验。这个计划的一个动机是在气相离子研究的详细信息与凝聚相有机金属化学、均相催化和生物系统的“真实的世界”之间建立更好的相关性。我们有意识地选择研究复杂性发展的简单系统，以定量评估金属化学的趋势。通过全面研究许多金属和许多配体的热化学，热力学数据中的趋势（周期性的，配体数量的变化，电子状态的变化）使我们能够超越获得数据的气相场所。 学生和博士后研究人员将参与这项研究。作为化学试剂，金属是生物系统的重要组成部分，作为酶的活性位点，有助于调节细胞功能和控制结构。 在技术上，金属被广泛用作催化剂，用于生产各种重要的精细化学品和燃料。 此外，核废料的清理和去污需要专门设计的分子，以选择性地与某些金属相互作用。 该项目所做的研究旨在提供有关金属与生物系统和化学工业相关的化学成分相互作用强度的基本信息。 这是最容易通过检查模型系统的复杂性进展。 这允许在此信息的趋势进行定量评估，这使得更复杂的化学环境的预测能力的发展。 在这项工作中，被称为引导离子束串联质谱仪的专门设备被用来检查金属离子与各种化学物质的相互作用。 这可以在单个分子上完成，从而可以消除来自环境的干扰相互作用。 这使得研究能够集中于阐明控制相互作用的特定因素。 与理论的密切合作提供了额外的洞察力，并提供了必要的预测能力。这项研究将与学生和博士后研究人员一起进行，他们因此接受培训，为深造或进入科学/技术工作队伍做准备。