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Hammes-Schiffer, Sharon Makri, Nancy Vura-Weis, Joshua Olshansky, Lisa Karippara Harshan, Aparna 2019-02-08T18:39:41Z 2019-02-08T18:39:41Z 2021-02-09T10:15:34Z 2018-10-01 2018-12 Proton-coupled electron transfer (PCET) plays an important role in a variety of electrochemical and photo-excited reactions occurring in molecular, material, and biological systems. In this thesis, the role of PCET in hydrogen evolution molecular electrocatalysts, and iron-doped nickel-oxyhydroxide thin films used for oxygen evolution reaction, are explored by means of quantum chemistry. Detailed electronic structural analysis performed using density functional theory is used to provide atomic level understanding of these catalytic systems. The electron-proton nonadiabaticity of PCET process is investigated for the phenoxyl/phenol self-exchange reaction, and the results show that the vibronic coupling is dependent on the molecular geometry. This diagnostic is important for the calculation of PCET rate constants. The rate constants and kinetic isotope effects for concerted PCET in a set of hydroquinone derivatives are calculated and analyzed in comparison with experimental data. Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2020-12-01 The student, Aparna Karippara Harshan, accepted the attached license on 2018-09-28 at 10:38. The student, Aparna Karippara Harshan, submitted this Dissertation for approval on 2018-09-28 at 12:24. This Dissertation was approved for publication on 2018-10-01 at 09:56. DSpace SAF Submission Ingestion Package generated from Vireo submission #13025 on 2019-02-08 at 11:38:08 Made available in DSpace on 2019-02-08T18:39:41Z (GMT). No. of bitstreams: 2 KARIPPARAHARSHAN-DISSERTATION-2018.pdf: 20519055 bytes, checksum: 6cf1ec8fe23226bddfcaa473e9931e35 (MD5) LICENSE.txt: 4228 bytes, checksum: e6054f092801012810dbb9d0051e1152 (MD5) Previous issue date: 2018-10-01 Embargo set by: Seth Robbins for item 109922 Lift date: 2021-02-08T18:40:00Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 109922 Lift date: 2021-02-08T18:42:23Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 109922 Lift date: 2021-02-08T18:43:54Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 109922 Lift date: 2021-02-08T18:44:50Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system Limited Restriction Lifted for Item 109922 on 2021-02-09T10:15:34Z. application/pdf http://hdl.handle.net/2142/102896 en Copyright 2018 Aparna Karippara Harshan Proton-coupled electron transfer PCET Molecular electrocatalysts Density Functional Theory Hydrogen Evolution Reaction Oxygen Evolution Reaction Vibronic coupling Proton-coupled electron transfer in molecular and material catalysis text text Ph.D. Dissertation Chemistry Chemistry University of Illinois at Urbana-Champaign