Femtosecond Pump-Probe Spectroscopy of Trinuclear Transition Metal Mixed-Valence Complexes

David F. Watson; Howe Siang Tan; Elmar Schreiber; Carolyn J. Mordas; Andrew B. Bocarsly

doi:10.1021/jp0363038

Femtosecond Pump-Probe Spectroscopy of Trinuclear Transition Metal Mixed-Valence Complexes

David F. Watson, Howe Siang Tan, Elmar Schreiber, Carolyn J. Mordas, Andrew B. Bocarsly

Research output: Contribution to journal › Article › peer-review

29 Scopus citations

Abstract

The dynamics of relaxation following photoinduced metal-to-metal charge-transfer (MMCT) processes of the trinuclear mixed-valence complexes [(NC) ₅Ru ^II-CN-Pt ^IV(NH ₃) ₄-NC-Ru ^II(CN) ₅] ^4- and [(NC) ₅Fe ^II-CN-Pt ^IV(NH ₃) ₄-NC-Fe ^II(CN) ₅] ^4- were investigated with femtosecond pump-probe spectroscopy. Relaxation dynamics following photoinduced M(II) → Pt(IV) MMCT varied with solvent and the identity of the M(II) centers. The back-electron-transfer (BET) time scale of [(NC) ₅Ru ^II-CN-Pt ^IV(NH ₃) ₄-NC-Ru ^II(CN) ₅] ^4- ranged from 476 ± 23 fs in water to 1110 ± 288 fs in a water/DMSO mixture with mole fraction DMSO of 0.1. The time scale of vibrational relaxation in the ground state ranged from 1.5 to 2.7 ps. Electron-transfer and ground-state vibrational relaxation dynamics of [(NC) ₅Fe ^II-CN-Pt ^IV(NH ₃) ₄-NC-Fe ^II(CN) ₅] ^4- were convolved, with relaxation to ground and product electronic states occurring within 3.5 ps. The electron-transfer dynamics of both complexes are significantly slower than the solvation dynamics of water or DMSO. The solvent dependence of the BET time scale of [(NC) ₅Ru ^II-CN-Pt ^IV(NH ₃) ₄-NC-Ru ^II(CN) ₅] ^4- is attributed to solvent-induced movement of the ground-state potential energy surface and the resulting changes in the driving force for BET. These effects enable systematic control over both the quantum yield of photodissociation and the dynamics of relaxation following photoinduced MMCT.

Original language	English (US)
Pages (from-to)	3261-3267
Number of pages	7
Journal	Journal of Physical Chemistry A
Volume	108
Issue number	16
DOIs	https://doi.org/10.1021/jp0363038
State	Published - Apr 22 2004

All Science Journal Classification (ASJC) codes

Physical and Theoretical Chemistry

Access to Document

10.1021/jp0363038

Cite this

@article{758c2a67f2294b5eb5440355b2934b25,

title = "Femtosecond Pump-Probe Spectroscopy of Trinuclear Transition Metal Mixed-Valence Complexes",

abstract = "The dynamics of relaxation following photoinduced metal-to-metal charge-transfer (MMCT) processes of the trinuclear mixed-valence complexes [(NC) 5Ru II-CN-Pt IV(NH 3) 4-NC-Ru II(CN) 5] 4- and [(NC) 5Fe II-CN-Pt IV(NH 3) 4-NC-Fe II(CN) 5] 4- were investigated with femtosecond pump-probe spectroscopy. Relaxation dynamics following photoinduced M(II) → Pt(IV) MMCT varied with solvent and the identity of the M(II) centers. The back-electron-transfer (BET) time scale of [(NC) 5Ru II-CN-Pt IV(NH 3) 4-NC-Ru II(CN) 5] 4- ranged from 476 ± 23 fs in water to 1110 ± 288 fs in a water/DMSO mixture with mole fraction DMSO of 0.1. The time scale of vibrational relaxation in the ground state ranged from 1.5 to 2.7 ps. Electron-transfer and ground-state vibrational relaxation dynamics of [(NC) 5Fe II-CN-Pt IV(NH 3) 4-NC-Fe II(CN) 5] 4- were convolved, with relaxation to ground and product electronic states occurring within 3.5 ps. The electron-transfer dynamics of both complexes are significantly slower than the solvation dynamics of water or DMSO. The solvent dependence of the BET time scale of [(NC) 5Ru II-CN-Pt IV(NH 3) 4-NC-Ru II(CN) 5] 4- is attributed to solvent-induced movement of the ground-state potential energy surface and the resulting changes in the driving force for BET. These effects enable systematic control over both the quantum yield of photodissociation and the dynamics of relaxation following photoinduced MMCT.",

author = "Watson, {David F.} and Tan, {Howe Siang} and Elmar Schreiber and Mordas, {Carolyn J.} and Bocarsly, {Andrew B.}",

year = "2004",

month = apr,

day = "22",

doi = "10.1021/jp0363038",

language = "English (US)",

volume = "108",

pages = "3261--3267",

journal = "Journal of Physical Chemistry A",

issn = "1089-5639",

publisher = "American Chemical Society",

number = "16",

}

TY - JOUR

T1 - Femtosecond Pump-Probe Spectroscopy of Trinuclear Transition Metal Mixed-Valence Complexes

AU - Watson, David F.

AU - Tan, Howe Siang

AU - Schreiber, Elmar

AU - Mordas, Carolyn J.

AU - Bocarsly, Andrew B.

PY - 2004/4/22

Y1 - 2004/4/22

N2 - The dynamics of relaxation following photoinduced metal-to-metal charge-transfer (MMCT) processes of the trinuclear mixed-valence complexes [(NC) 5Ru II-CN-Pt IV(NH 3) 4-NC-Ru II(CN) 5] 4- and [(NC) 5Fe II-CN-Pt IV(NH 3) 4-NC-Fe II(CN) 5] 4- were investigated with femtosecond pump-probe spectroscopy. Relaxation dynamics following photoinduced M(II) → Pt(IV) MMCT varied with solvent and the identity of the M(II) centers. The back-electron-transfer (BET) time scale of [(NC) 5Ru II-CN-Pt IV(NH 3) 4-NC-Ru II(CN) 5] 4- ranged from 476 ± 23 fs in water to 1110 ± 288 fs in a water/DMSO mixture with mole fraction DMSO of 0.1. The time scale of vibrational relaxation in the ground state ranged from 1.5 to 2.7 ps. Electron-transfer and ground-state vibrational relaxation dynamics of [(NC) 5Fe II-CN-Pt IV(NH 3) 4-NC-Fe II(CN) 5] 4- were convolved, with relaxation to ground and product electronic states occurring within 3.5 ps. The electron-transfer dynamics of both complexes are significantly slower than the solvation dynamics of water or DMSO. The solvent dependence of the BET time scale of [(NC) 5Ru II-CN-Pt IV(NH 3) 4-NC-Ru II(CN) 5] 4- is attributed to solvent-induced movement of the ground-state potential energy surface and the resulting changes in the driving force for BET. These effects enable systematic control over both the quantum yield of photodissociation and the dynamics of relaxation following photoinduced MMCT.

AB - The dynamics of relaxation following photoinduced metal-to-metal charge-transfer (MMCT) processes of the trinuclear mixed-valence complexes [(NC) 5Ru II-CN-Pt IV(NH 3) 4-NC-Ru II(CN) 5] 4- and [(NC) 5Fe II-CN-Pt IV(NH 3) 4-NC-Fe II(CN) 5] 4- were investigated with femtosecond pump-probe spectroscopy. Relaxation dynamics following photoinduced M(II) → Pt(IV) MMCT varied with solvent and the identity of the M(II) centers. The back-electron-transfer (BET) time scale of [(NC) 5Ru II-CN-Pt IV(NH 3) 4-NC-Ru II(CN) 5] 4- ranged from 476 ± 23 fs in water to 1110 ± 288 fs in a water/DMSO mixture with mole fraction DMSO of 0.1. The time scale of vibrational relaxation in the ground state ranged from 1.5 to 2.7 ps. Electron-transfer and ground-state vibrational relaxation dynamics of [(NC) 5Fe II-CN-Pt IV(NH 3) 4-NC-Fe II(CN) 5] 4- were convolved, with relaxation to ground and product electronic states occurring within 3.5 ps. The electron-transfer dynamics of both complexes are significantly slower than the solvation dynamics of water or DMSO. The solvent dependence of the BET time scale of [(NC) 5Ru II-CN-Pt IV(NH 3) 4-NC-Ru II(CN) 5] 4- is attributed to solvent-induced movement of the ground-state potential energy surface and the resulting changes in the driving force for BET. These effects enable systematic control over both the quantum yield of photodissociation and the dynamics of relaxation following photoinduced MMCT.

UR - http://www.scopus.com/inward/record.url?scp=2342459691&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=2342459691&partnerID=8YFLogxK

U2 - 10.1021/jp0363038

DO - 10.1021/jp0363038

M3 - Article

AN - SCOPUS:2342459691

SN - 1089-5639

VL - 108

SP - 3261

EP - 3267

JO - Journal of Physical Chemistry A

JF - Journal of Physical Chemistry A

IS - 16

ER -

Femtosecond Pump-Probe Spectroscopy of Trinuclear Transition Metal Mixed-Valence Complexes

Abstract

All Science Journal Classification (ASJC) codes

Access to Document

Other files and links

Fingerprint

Cite this