Chemistry Seminar

Rebecca Hopkins (’20, CHEM), PhD candidate, The University of Pittsburgh

Two-dimensional infrared spectroscopy to characterize anion transport in a highly-ordered polymeric anion exchange membrane 

Becky Hopkin’s research focuses on physical chemistry. Her I.S. advisor was Karl Feierabend, PhD. She is a member of The Anna Group at the University of Pittsburgh.

Two dimensional infrared spectroscopy (2DIR) is an ultrafast spectroscopic technique that uses laser pulse sequences to track changes to molecular vibrational excited states on the femtosecond to picosecond (10^-15 to 10^-12 seconds) timescale. Due to the sensitivity of vibrational excitations to the local molecular environment, vibrational probes can be used to track ultrafast interactions between the probe and its microenvironment by tracking observables like vibrational excitation lifetime and spectral diffusion timescales. In this work, this ability of 2DIR is leveraged to provide a molecular-level understanding of anion transport in novel highly-ordered polymeric anion exchange membranes. A combination of 2DIR, molecular dynamics simulation, and electronic impedance spectroscopy forms a bridge between the microscopic interactions of anions in the membranes with the macroscopic property of conductivity. In this seminar, expect to learn about 2DIR as a technique and its application to the problem of ion transport within anion exchange membranes. 

Lunch with Becky

Students are invited to meet with Becky Hopkins over lunch in Severance 105 following the lecture. RSVP is appreciated, although not required: https://forms.office.com/r/uNRfRd16he