Characterizing the Solvated Structure of Photoexcited [Os(terpy)2]2+ with X-ray Transient Absorption Spectroscopy and DFT Calculations

Xiaoyi Zhang, Mátyás Imre Pápai, Klaus Braagaard Møller, Jianxin Zhang, Sophie E. Canton

Research output: Contribution to journalJournal articleResearchpeer-review

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Abstract

Characterizing the geometric and electronic structures of individual photoexcited dye molecules in solution is an important step towards understanding the interfacial properties of photo-active electrodes. The broad family of "red sensitizers" based on osmium(II) polypyridyl compounds often undergoes small photo-induced structural changes which are challenging to characterize. In this work, X-ray transient absorption spectroscopy with picosecond temporal resolution is employed to determine the geometric and electronic structures of the photoexcited triplet state of [Os(terpy)2]2+ (terpy: 2,2':6',2″-terpyridine) solvated in methanol. From the EXAFS analysis, the structural changes can be characterized by a slight overall expansion of the first coordination shell [OsN6]. DFT calculations supports the XTA results. They also provide additional information about the nature of the molecular orbitals that contribute to the optical spectrum (with TD-DFT) and the near-edge region of the X-ray spectra.
Original languageEnglish
JournalMolecules
Volume21
Issue number2
Number of pages9
ISSN1420-3049
DOIs
Publication statusPublished - 2016

Bibliographical note

This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Keywords

  • X-ray transient absorption spectroscopy
  • Excited-state
  • Osmium polypyridyl complex

Cite this

@article{448d89e1c76c4a4cadd9bd11531666fa,
title = "Characterizing the Solvated Structure of Photoexcited [Os(terpy)2]2+ with X-ray Transient Absorption Spectroscopy and DFT Calculations",
abstract = "Characterizing the geometric and electronic structures of individual photoexcited dye molecules in solution is an important step towards understanding the interfacial properties of photo-active electrodes. The broad family of {"}red sensitizers{"} based on osmium(II) polypyridyl compounds often undergoes small photo-induced structural changes which are challenging to characterize. In this work, X-ray transient absorption spectroscopy with picosecond temporal resolution is employed to determine the geometric and electronic structures of the photoexcited triplet state of [Os(terpy)2]2+ (terpy: 2,2':6',2″-terpyridine) solvated in methanol. From the EXAFS analysis, the structural changes can be characterized by a slight overall expansion of the first coordination shell [OsN6]. DFT calculations supports the XTA results. They also provide additional information about the nature of the molecular orbitals that contribute to the optical spectrum (with TD-DFT) and the near-edge region of the X-ray spectra.",
keywords = "X-ray transient absorption spectroscopy, Excited-state, Osmium polypyridyl complex",
author = "Xiaoyi Zhang and P{\'a}pai, {M{\'a}ty{\'a}s Imre} and M{\o}ller, {Klaus Braagaard} and Jianxin Zhang and Canton, {Sophie E.}",
note = "This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.",
year = "2016",
doi = "10.3390/molecules21020235",
language = "English",
volume = "21",
journal = "Molecules",
issn = "1420-3049",
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Characterizing the Solvated Structure of Photoexcited [Os(terpy)2]2+ with X-ray Transient Absorption Spectroscopy and DFT Calculations. / Zhang, Xiaoyi; Pápai, Mátyás Imre; Møller, Klaus Braagaard; Zhang, Jianxin; Canton, Sophie E.

In: Molecules, Vol. 21, No. 2, 2016.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Characterizing the Solvated Structure of Photoexcited [Os(terpy)2]2+ with X-ray Transient Absorption Spectroscopy and DFT Calculations

AU - Zhang, Xiaoyi

AU - Pápai, Mátyás Imre

AU - Møller, Klaus Braagaard

AU - Zhang, Jianxin

AU - Canton, Sophie E.

N1 - This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PY - 2016

Y1 - 2016

N2 - Characterizing the geometric and electronic structures of individual photoexcited dye molecules in solution is an important step towards understanding the interfacial properties of photo-active electrodes. The broad family of "red sensitizers" based on osmium(II) polypyridyl compounds often undergoes small photo-induced structural changes which are challenging to characterize. In this work, X-ray transient absorption spectroscopy with picosecond temporal resolution is employed to determine the geometric and electronic structures of the photoexcited triplet state of [Os(terpy)2]2+ (terpy: 2,2':6',2″-terpyridine) solvated in methanol. From the EXAFS analysis, the structural changes can be characterized by a slight overall expansion of the first coordination shell [OsN6]. DFT calculations supports the XTA results. They also provide additional information about the nature of the molecular orbitals that contribute to the optical spectrum (with TD-DFT) and the near-edge region of the X-ray spectra.

AB - Characterizing the geometric and electronic structures of individual photoexcited dye molecules in solution is an important step towards understanding the interfacial properties of photo-active electrodes. The broad family of "red sensitizers" based on osmium(II) polypyridyl compounds often undergoes small photo-induced structural changes which are challenging to characterize. In this work, X-ray transient absorption spectroscopy with picosecond temporal resolution is employed to determine the geometric and electronic structures of the photoexcited triplet state of [Os(terpy)2]2+ (terpy: 2,2':6',2″-terpyridine) solvated in methanol. From the EXAFS analysis, the structural changes can be characterized by a slight overall expansion of the first coordination shell [OsN6]. DFT calculations supports the XTA results. They also provide additional information about the nature of the molecular orbitals that contribute to the optical spectrum (with TD-DFT) and the near-edge region of the X-ray spectra.

KW - X-ray transient absorption spectroscopy

KW - Excited-state

KW - Osmium polypyridyl complex

U2 - 10.3390/molecules21020235

DO - 10.3390/molecules21020235

M3 - Journal article

VL - 21

JO - Molecules

JF - Molecules

SN - 1420-3049

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