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Title: Can Excited State Electronic Coherence Be Tuned via Molecular Structural Modification? A First-Principles Quantum Electronic Dynamics Study of Pyrazolate-Bridged Pt(II) Dimers

Abstract

Materials and molecular systems exhibiting long-lived electronic coherence can facilitate coherent transport, opening the door to efficient charge and energy transport beyond traditional methods. Recently, signatures of a possible coherent, recurrent electronic motion were identified in femtosecond pump-probe spectroscopy experiments on a binuclear platinum complex, where a persistent periodic beating in the transient absorption signal’s anisotropy was observed. In this study, we investigate the excitonic dynamics that underlie the suspected electronic coherence for a series of binuclear platinum complexes exhibiting a range of interplatinum distances. Results suggest that the long-lived coherence can only result when competitive electronic couplings are in balance. At longer Pt-Pt distances, the electronic couplings between the two halves of the binuclear system weaken, and exciton localization and recombination is favored on short time scales. For short Pt-Pt distances, electronic couplings between the states in the coherent superposition are stronger than the coupling with other excitonic states, leading to long-lived coherence.

Authors:
; ; ; ORCiD logo; ; ORCiD logo; ; ORCiD logo
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1406558
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory; Journal Volume: 121; Journal Issue: 9
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Lingerfelt, David B., Lestrange, Patrick J., Radler, Joseph J., Brown-Xu, Samantha E., Kim, Pyosang, Castellano, Felix N., Chen, Lin X., and Li, Xiaosong. Can Excited State Electronic Coherence Be Tuned via Molecular Structural Modification? A First-Principles Quantum Electronic Dynamics Study of Pyrazolate-Bridged Pt(II) Dimers. United States: N. p., 2017. Web. doi:10.1021/acs.jpca.6b12099.
Lingerfelt, David B., Lestrange, Patrick J., Radler, Joseph J., Brown-Xu, Samantha E., Kim, Pyosang, Castellano, Felix N., Chen, Lin X., & Li, Xiaosong. Can Excited State Electronic Coherence Be Tuned via Molecular Structural Modification? A First-Principles Quantum Electronic Dynamics Study of Pyrazolate-Bridged Pt(II) Dimers. United States. doi:10.1021/acs.jpca.6b12099.
Lingerfelt, David B., Lestrange, Patrick J., Radler, Joseph J., Brown-Xu, Samantha E., Kim, Pyosang, Castellano, Felix N., Chen, Lin X., and Li, Xiaosong. Fri . "Can Excited State Electronic Coherence Be Tuned via Molecular Structural Modification? A First-Principles Quantum Electronic Dynamics Study of Pyrazolate-Bridged Pt(II) Dimers". United States. doi:10.1021/acs.jpca.6b12099.
@article{osti_1406558,
title = {Can Excited State Electronic Coherence Be Tuned via Molecular Structural Modification? A First-Principles Quantum Electronic Dynamics Study of Pyrazolate-Bridged Pt(II) Dimers},
author = {Lingerfelt, David B. and Lestrange, Patrick J. and Radler, Joseph J. and Brown-Xu, Samantha E. and Kim, Pyosang and Castellano, Felix N. and Chen, Lin X. and Li, Xiaosong},
abstractNote = {Materials and molecular systems exhibiting long-lived electronic coherence can facilitate coherent transport, opening the door to efficient charge and energy transport beyond traditional methods. Recently, signatures of a possible coherent, recurrent electronic motion were identified in femtosecond pump-probe spectroscopy experiments on a binuclear platinum complex, where a persistent periodic beating in the transient absorption signal’s anisotropy was observed. In this study, we investigate the excitonic dynamics that underlie the suspected electronic coherence for a series of binuclear platinum complexes exhibiting a range of interplatinum distances. Results suggest that the long-lived coherence can only result when competitive electronic couplings are in balance. At longer Pt-Pt distances, the electronic couplings between the two halves of the binuclear system weaken, and exciton localization and recombination is favored on short time scales. For short Pt-Pt distances, electronic couplings between the states in the coherent superposition are stronger than the coupling with other excitonic states, leading to long-lived coherence.},
doi = {10.1021/acs.jpca.6b12099},
journal = {Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory},
number = 9,
volume = 121,
place = {United States},
year = {Fri Feb 24 00:00:00 EST 2017},
month = {Fri Feb 24 00:00:00 EST 2017}
}
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