Comparative Study of the High Harmonic Spectra of Transition Metal Compounds

激光技术的进步为高次谐波产生（HHG）的研究开辟了新的前沿，HHG是一种强激光与材料相互作用产生更高频率的光的现象。该项目旨在利用HHG更好地了解过渡金属化合物的化学性质，这些化合物在各种化学过程中至关重要，并具有广泛的工业应用。过渡金属化合物具有有趣的性质，部分原因是它们复杂的电子结构。通过探索过渡金属化合物的HHG光谱，这项研究有助于推进我们对这些材料的理解，这对化学和材料科学的创新具有广泛的意义。此外，该项目还包括通过培训下一代科学家为国家利益服务的教育部分。它将前沿研究融入课堂，并积极吸引本科生，为他们提供宝贵的经验。通过与当地学校的合作，该项目还旨在激发年轻学生并培养整个社区对科学的欣赏。该项目重点研究含有羰基，氰化物和氯化物基团的过渡金属化合物的HHG光谱。该研究采用含时密度泛函理论（TDDFT）计算研究了几种化合物，如Ni（CO）4，V（CO）6，Ni（CN）2，Ni（CN）4^3-和NiCl 4^2-。分析将包括理解在HHG光谱的变化方面的金属的性质，配体，自旋状态，和配位几何形状。此外，该项目将探测偏离高次谐波截止定律的情况，分析电离势以下的共振增强高次谐波发射，并探索金属和配体之间的电荷转移。这种全面的方法将有助于理解不同轨道上多个电子的相位关系如何偏离过渡金属化合物中的单活性电子（SAE）预测。此外，该项目还涉及对主要研究者和合作者开发的TDDFT方法进行系统的基准测试和改进，从而进一步加深对过渡金属化合物复杂电子结构和多电子动力学的理解。和光学物理理论程序和既定的程序，以刺激竞争力的研究（EPSCoR）该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Advancements in laser technology have opened new frontiers in the study of high harmonic generation (HHG), a phenomenon where intense laser light interacting with materials produces higher frequencies of light. This project aims to harness HHG to better understand the chemistry of transition metal compounds, which are essential in various chemical processes and have extensive industrial applications. Transition metal compounds have intriguing properties, partly due to their complex electronic structures. By exploring the HHG spectra of transition metal compounds, this research contributes to advancing our understanding of these materials, which can have wide-ranging implications for innovations in chemistry and materials science. Additionally, this project includes educational components that will serve the national interest by training the next generation of scientists. It integrates cutting-edge research into classrooms and actively engages undergraduate students, providing them with invaluable experience. Through collaborations with local schools, this project also seeks to inspire younger students and foster a community-wide appreciation for science.This project focuses on examining the HHG spectra of transition metal compounds containing carbonyl, cyanide, and chloride groups. The study employs time-dependent density functional theory (TDDFT) calculations to investigate several compounds such as Ni(CO)4, V(CO)6, Ni(CN)2, Ni(CN)4^3-, and NiCl4^2-. The analyses will encompass understanding the variations in the HHG spectra in terms of the metal's properties, ligands, spin states, and coordination geometries. Furthermore, the project will probe the deviations from the high harmonic cutoff law, analyze resonance-enhanced high harmonic emissions below the ionization potential, and explore charge transfer between the metal and ligands. This comprehensive approach will help in understanding how the phase relations of multiple electrons on different trajectories can deviate from the single-active-electron (SAE) predictions in transition metal compounds. Moreover, it involves systematic benchmarking and improvement of the TDDFT methods developed by the PI and collaborators, which can further deepen insights into complex electronic structures and multi-electron dynamics in transition metal compounds.This project is jointly funded by the Atomic, Molecular, and Optical Physics Theory Program and the Established Program to Stimulate Competitive Research (EPSCoR).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.