Spectroscopy of Carbon Cluster Cations

在化学系化学结构、动力学和机理A(CSDM-A)项目的支持下，迈克尔·邓肯教授和他在佐治亚大学的学生将研究小碳分子。在分子水平上理解碳材料的结构和功能是化学和工程面临的持续挑战。碳纤维、石墨烯薄片或富勒烯笼可用作微电子和太阳能发电的材料，而金属-碳材料构成了现代电池技术的基础。碳分子离子可能存在于星际气体云中，在天体化学中发挥着重要作用。该项目探索了制造碳分子的新方法，并使用激光光谱分析来确定其结构和成键特性。所获得的见解有助于碳基材料的设计和理解。这项工作对学生进行激光和真空技术、电子学、光谱学、质谱学和计算化学方面的培训，为他们在化学工业、大学教员职位或政府实验室的科学家职业生涯做准备。邓肯教授还指导职业生涯早期的教授，其中许多人来自代表性不足的团体，帮助他们开发物理化学实验室实验的新方法。本研究研究了分子碳簇阳离子及其与金属原子和小分子的化学相互作用。冷碳团簇离子及其络合物是通过激光蒸发耦合到超音速分子束在气相中产生的。无碰撞环境允许内部结构不受液体或固体环境的干扰。用质谱仪选择具有特定组成的离子，并用红外和紫外可见激光光谱结合计算量子化学来研究它们的结构。在红外区测量了碳骨架振动和分子吸附的特征光谱模式。可广泛调谐的紫外可见激光使电子光谱学的新研究成为可能。光碎片成像实验补充了光谱，揭示了成键能量学。这些实验对电子结构和成键产生了新的化学见解，并为预测结构、振动模式和激发电子态的计算量子化学提供了基准。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Chemical Structure, Dynamics, and Mechanisms A (CSDM-A) program of the Chemistry Division, Professor Michael Duncan and his students at the University of Georgia will study small carbon molecules. The molecular-level understanding of structure and function of carbon materials are ongoing challenges for chemistry and engineering. Carbon fibers, graphene sheets, or fullerene cages have applications as materials for microelectronics and solar energy generation, and metal-carbon materials form the basis for modern battery technology. Carbon molecular ions are likely present in interstellar gas clouds, playing an important role in astrochemistry. This project explores new ways to make carbon molecules and employs laser spectroscopy to determine their structures and bonding properties. The insights gained facilitate the design and understanding of carbon-based materials. The work trains students in laser and vacuum technology, electronics, spectroscopy, mass spectrometry, and computational chemistry, preparing them for careers in the chemical industry, university faculty positions, or as scientists in government labs. Professor Duncan also mentors early-career professors, many of them members of underrepresented groups, to help them develop new approaches for physical chemistry laboratory experiments. This research investigates molecular carbon cluster cations and their chemical interactions with metal atoms and small molecules. Cold carbon cluster ions and their complexes are produced in the gas phase with laser vaporization coupled to a supersonic molecular beam. The collision-free environment allows intrinsic structures unperturbed by liquid or solid surroundings. Ions with a specific composition are selected with a mass spectrometer, and their structures are studied with infrared and UV-visible laser spectroscopy, complemented with computational quantum chemistry. Characteristic spectral patterns are measured in the infrared region for carbon framework vibrations and those of molecular adsorbates. Broadly tunable UV-visible lasers allow new studies of electronic spectroscopy. Photofragment imaging experiments complement the spectroscopy, revealing bonding energetics. These experiments yield new chemical insights into electronic structure and bonding and provide benchmarks for computational quantum chemistry which predicts structures, vibrational patterns, and excited electronic states.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.