Mechanistic studies of photo-induced proton-coupled electron transfer and oxygen atom transfer reactions in model systems

Time-resolved optical spectroscopy has been employed for mechanistic studies in model systems designed to undergo photo-induced proton-coupled electron transfer (PCET) and oxygen atom transfer (OAT) reactions, both of which are important to energy conversion chemistry (Chapter I). The effect of coupling proton transfer (PT) to electron transfer (ET) depends on their spatial configuration, thus model PCET systems must control both. Noncovalent amidinium-carboxylate PT interfaces are used assemble an electron D/A pairs (D = donor, A = acceptor), establishing uni-directional ET and PT coordinates. A highly conjugated porphyrin-amidinium derivative bears optical signatures that report on the structure of PT interfaces formed upon association with carboxylate acceptors (Chapter II). PT is supported within the interface and the mediating proton's position is sensitive to the peripheral electronic structure. Transient absorption (TA) spectroscopy is applied to a related porphyrin D---[H+]---A assembly, where ---[H+]--- = amidinecarboxylic acid (Chapter III). Specific probe wavelengths are targeted in order to amplify the optical signatures of PCET over those of competing quenching mechanisms.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemistry.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Hodgkiss, Justin M. (Justin Mark), 1978-

Advisor dc:contributor.advisor

• Daniel G. Nocera.

• Chemistry.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/38539

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/38539