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，这些化合物在各种化学过程中是必不可少的，并具有广泛的工业应用。过渡金属化合物具有耐人寻味的性质，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谱，本研究有助于增进我们对这些材料的理解，这可能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。它将尖端研究融入课堂，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，这个项目还试图激励年轻学生，培养全社会对科学的欣赏。这个项目重点研究含有羰基、氰化物和氯基的过渡金属化合物的HHG光谱。本研究采用含时密度泛函理论(TDDFT)方法对Ni(CO)4、V(CO)6、Ni(CN)2、Ni(CN)4^3-和NiCl4^2-等几种化合物进行了计算。这些分析将包括了解HHG光谱在金属的性质、配体、自旋态和配位几何方面的变化。此外，该项目还将探索高次谐波截止定律的偏差，分析电离势以下共振增强的高次谐波发射，并探索金属与配体之间的电荷转移。这种综合的方法将有助于理解过渡金属化合物中不同轨道上的多电子的相关系如何偏离单活性电子(SAE)的预测。此外，它还包括系统的基准测试和改进由PI和合作者开发的TDDFT方法，这可以进一步加深对过渡金属化合物中复杂的电子结构和多电子动力学的洞察。该项目由原子、分子和光学物理理论计划和既定的刺激竞争研究计划(EPSCoR)联合资助。该奖项反映了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。

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.