CAREER: Revealing the Interplay of Spin and Charge Degrees of Freedom in Iron Complexes With Redox Active Ligands

In this CAREER project, jointly funded by the Chemical Mechanism, Function, and Properties (CMFP) Program of the Chemistry Division and the Established Program to Stimulate Competitive Research (EPSCoR), Professor Sebastian Stoian of the Department of Chemistry at the University of Idaho is developing new iron-based, multifunctional magnetic materials with tailored properties. The goal of this research is to map out subtle interactions between the building blocks of these materials. This project seeks to advance our knowledge of complex materials encountered in magnetism and catalysis, addressing important challenges in quantum computing and energy production. The project provides advanced research training to graduate and undergraduate students and includes a curriculum development plan for enhancing the computational chemistry competencies of undergraduate students. Finally, research experiences for teachers will also be part of the funded project as outreach activities aimed at boosting the STEM motivation of high-school students throughout Northern Idaho. Chemical species featuring metal ions supported by redox active ligands play critical roles in the catalytic cycles of many enzymes and synthetic systems. Yet, the oxidation and spin states of the metal sites and their supporting ligands are often difficult to assess. In this project, Professor Stoian’s team will use a spectroscopy-guided approach to synthesize and investigate a series of iron compounds with selected redox-active ligands. To elucidate the intricate interplay between spin and charge degrees of freedom in such species, the planned research relies on the unique capabilities of field-dependent Mössbauer spectroscopy, complemented by electron paramagnetic resonance and computational studies, to probe the electronic structure of iron sites in complex chemical environments. The target materials could exhibit a number of desirable properties including magnetic bistability and oxygen activation, as well as quantum entanglement of local metal spin states induced by their interaction with open-shell, redox-active ligands. 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.