Understanding the reactive site in catalysis through spectroscopy of clusters, reactive intermediates and transition states
Abstract
The field of catalysis represents one of the most prominent examples of how fundamental science positively impacts society. Catalysis is generally concerned with the behavior of bulk materials, but the underlying chemistry remains a molecular-scale phenomenon. One of the primary goals of physical chemistry is to gain a molecular-level understanding of the catalytic sites where chemical reactions take place and to ascertain how catalysts lower the energies of transition states in these reactions. As these sites typically consist of small groups of atoms, gas phase molecular and ionic clusters serve as tractable model systems for probing the underlying factors which give rise to catalytic behavior. This proposal outlines multiple paths to new insights into the catalytic site, using high resolution photoelectron spectroscopy and infrared photodissociation of gas phase cluster anions to probe the reactive intermediates formed during reactions of transition metal and metal oxide clusters with H2O, CH3OH, and CH4. The splitting of CH3OH on metal oxide clusters is of particular interest, as is the role played Pt atoms and bimetallic metal oxides in CH4 activation. Similar methodology will be carried on clusters that are of particular interest to AFOSR and AFRL, including metal-monoxide cluster anions, meteorite constituents, and gas phase studies of electrides. A new capability in which anions are vibrationally excited prior to photodetachment will enable one to explore the vibrational spectroscopy and dynamics of metal oxide clusters. It will also enable a new generation of transition state spectroscopy studies, because photodetachment of vibrationally excited anions will enable one to probe previously inaccessible regions of the neutral transition state region in unimolecular and bimolecular reactions.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 06, 2024
- Source ID
- FA95502310545
Entities
People
- Daniel Neumark
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of California Regents