A radical approach: Paramagnetic Nickel and Palladium species in organometallic catalysis

Paramagnetic Ni and Pd complexes have been proposed to play an important role in a number of C-C and C-heteroatom bond formation reactions, as well as a series of oxidative and reductive transformations. In this context, a series of uncommon mononuclear Pd(III) complexes have been synthesized and their oxidative reactivity was investigated. In addition, organometallic Ni(III) complexes relevant to cross-coupling reactions have been isolated and their catalytic reactivity was studied in detail.

Spin, Protons, and Pathways: Controlling Electron Transfer in Electrocatalysis of Coordination Complexes

Proton-coupled electron transfer (PCET) is a central principle for catalytic hydrogen and CO2 transformations. In this seminar, I will discuss how internal factors of metal–ligand identity, coordination geometry, and spin states interact with external influences such as pKa of proton donors and applied potentials to shape PCET pathways. Our studies with Co complexes show that spin interactions critically govern electron transfer, while investigations of Fe complexes reveal how maintaining the low spin states enables rapid, efficient multi-electron processes.

TBD

Designing for Disorder: Electrocatalytic Synthesis with Interfacial Control

Abstract: Chemical synthesis driven by electricity offers a scalable, decentralized, and energy-efficient route to furnish value-added products – from fuels to complex molecules. Maximizing reaction efficiency and durability requires immobilized catalytic active sites on electrodes, resulting in dispersed and non-uniform sites. This heterogeneity challenges iterative optimization of reactivity through traditional catalyst modifications, which rely on uniform, singular active sites.

Investigating Heme Superoxo and Peroxo Mediated Pathways of Heme Enzymes Using Functional Synthetic Mimics

Abstract: Heme enzymes mediate a plethora of paramount reaction pathways in a wide variety of organisms, including humans, wherein dioxygen activating heme enzymes are prevalent.[1, 2] Interestingly, a number of pivotal geometric and electronic parameters in concert fine-tune such heme centers for their specialized reactivities, which strongly modulate the reactivity properties of their relevant reaction intermediates.

Harnessing static and dynamic disorder for solid-state ion transport

Abstract: Mastery over solid-state ion transport is paramount for broad diversity of applications and technologies, including batteries, fuel cells, neuromorphic computing, and beyond. Disorder – both static and dynamic – plays a crucial role in dictating ion diffusion in the solid state. Our work seeks to understand and harness disorder across time and length scales to impact ion transport processes. The argyrodites Li6PS5X (X = Cl–, Br–, I–, CN–) are amenable to a large degree of both static and dynamic disorder that conspire to influence mobile ion dynamics.

Spin-phonon and spin-electric coupling in magnetic molecules

Abstract: Molecules represent the smallest arbitrarily-designable quantum entities and they show promise for several applications in quantum science. Some difficulties arise from their large number of degrees of freedom which lead to unfavourable spin-phonon coupling pathways, but at the same time they offer significant opportunities, for example tuning the spin-electric coupling that can arise in the presence of significant spin-orbit coupling.

Functional Roles for Non-Canonical Electronic Structures of Iron-Sulfur Clusters

Iron-sulfur proteins are found in all kingdoms of life and carry out some of the most kinetically challenging reactions in the biosphere. In this talk, I will discuss my group’s efforts to understand how the remarkable functions of these proteins derive from the unique electronic structures of their iron-sulfur clusters. Emphasis will be placed on the use of synthetic models to understand how iron-sulfur clusters—typically comprised of mid-valent, high-spin iron centers—perform chemistry reminiscent of low-valent iron, specifically in the binding and activation of π acids such as N2 and CO.

Innovative Approaches towards Clean, Sustainable, and Affordable Catalysis: Exploring the Rational Design of Molecular Catalysts

Abstract: The development of alternative energy sources beyond fossil fuels relies on the activation of small molecules (e.g., H2, O2, CH4) through multi-electron, multi-proton reaction sequences. However, these processes face high kinetic barriers, requiring catalysts capable of mediating multi-electron reactivity.

UCI Department of Chemistry

Inorganic Seminar