Chemistry Masters Candidate Thesis Defense Presentation
Isaac Sarfo, Candidate
Dr. Sergiy Rosokha (Advisor)
"Covalency of Strong Halogen Bonds and Its Role in Electron Transfer"
Thursday, June 11th, 12pm
Foundational Science Building - FB-253
Abstract: Halogen bonding ( refers to the attractive interaction between electron rich species (XB Acceptor) and covalently bound halogen atoms (XB Donor), as shown in the figure above XB has emerged as a key noncovalent interaction in supramolecular chemistry due to its broad applications in crystal engineering, molecular recognition, conducting and magnetic materials, and catalysis As a highly tunable analog to hydrogen bonding, XB can be modulated by increasing the electrophilicity of the XB donor, which induces a transition from a weak supramolecular regime to a strong interaction with significant covalent character While XB is traditionally viewed as a purely electrostatic attraction, molecular orbital interactions, specifically electronic coupling, are crucial for driving the formation of strong XB complexes The H DA mediated by the halogen bond lowers the activation energy barrier and facilitates electron transfer, driving subsequent chemical transformations Theoretical activation barriers, and rate constants were determined using the Marcus and Mulliken Hush electron transfer models, with the latter showing excellent agreement with experimental rate constants due to its robust inclusion of strong electronic coupling.