Robust Inclusion Complexes of Crown Ether Fused Tetrathiafulvalenes with Li+@C-60 to Afford Efficient Photodriven Charge Separation

M. Supur, Y. Kawashima, K. R. Larsen, K. Ohkubo, J. O. Jeppesen, S. Fukuzumi

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Resumé

Inclusion complexes of benzo-and dithiabenzocrown ether functionalized monopyrrolotetrathiafulvalene (MPTTF) molecules were formed with Li+@C-60 (1 center dot Li+@C-60 and 2 center dot Li+@C-60). The strong complexation has been quantified by high binding constants that exceed 10(6) (-1)(M) obtained by UV/Vis titrations in benzonitrile (PhCN) at room temperature. On the basis of DFT studies at the B3LYP/6-311G(d,p) level, the orbital interactions between the crown ether moieties and the p surface of the fullerene together with the endohedral Li+ have a crucial role in robust complex formation. Interestingly, complexation of Li+@C-60 with crown ethers accelerates the intersystem crossing upon photoexcitation of the complex, thereby yielding 3(Li+@C-60)*, when no charge separation by means of 1Li(+)@C-60* occurs. Photoinduced charge separation by means of 3Li(+)@C-60* with lifetimes of 135 and 120 ms for 1 center dot Li+@C-60 and 2 center dot Li+@C-60, respectively, and quantum yields of 0.82 in PhCN have been observed by utilizing time-resolved transient absorption spectroscopy and then confirmed by electron paramagnetic resonance measurements at 4 K. The difference in crown ether structures affects the binding constant and the rates of photoinduced electron-transfer events in the corresponding complex.
OriginalsprogEngelsk
TidsskriftChemistry: A European Journal
Vol/bind20
Udgave nummer43
Sider (fra-til)13976-13983
ISSN0947-6539
DOI
StatusUdgivet - 2014

Citer dette

@article{7c5f5d4326d14836b39b0b988c97bf48,
title = "Robust Inclusion Complexes of Crown Ether Fused Tetrathiafulvalenes with Li+@C-60 to Afford Efficient Photodriven Charge Separation",
abstract = "Inclusion complexes of benzo-and dithiabenzocrown ether functionalized monopyrrolotetrathiafulvalene (MPTTF) molecules were formed with Li+@C-60 (1 center dot Li+@C-60 and 2 center dot Li+@C-60). The strong complexation has been quantified by high binding constants that exceed 10(6) (-1)(M) obtained by UV/Vis titrations in benzonitrile (PhCN) at room temperature. On the basis of DFT studies at the B3LYP/6-311G(d,p) level, the orbital interactions between the crown ether moieties and the p surface of the fullerene together with the endohedral Li+ have a crucial role in robust complex formation. Interestingly, complexation of Li+@C-60 with crown ethers accelerates the intersystem crossing upon photoexcitation of the complex, thereby yielding 3(Li+@C-60)*, when no charge separation by means of 1Li(+)@C-60* occurs. Photoinduced charge separation by means of 3Li(+)@C-60* with lifetimes of 135 and 120 ms for 1 center dot Li+@C-60 and 2 center dot Li+@C-60, respectively, and quantum yields of 0.82 in PhCN have been observed by utilizing time-resolved transient absorption spectroscopy and then confirmed by electron paramagnetic resonance measurements at 4 K. The difference in crown ether structures affects the binding constant and the rates of photoinduced electron-transfer events in the corresponding complex.",
author = "M. Supur and Y. Kawashima and Larsen, {K. R.} and K. Ohkubo and Jeppesen, {J. O.} and S. Fukuzumi",
year = "2014",
doi = "10.1002/chem.201402449",
language = "English",
volume = "20",
pages = "13976--13983",
journal = "Chemistry: A European Journal",
issn = "0947-6539",
publisher = "Wiley - V C H Verlag GmbH & Co. KGaA",
number = "43",

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Robust Inclusion Complexes of Crown Ether Fused Tetrathiafulvalenes with Li+@C-60 to Afford Efficient Photodriven Charge Separation. / Supur, M.; Kawashima, Y.; Larsen, K. R.; Ohkubo, K.; Jeppesen, J. O.; Fukuzumi, S.

I: Chemistry: A European Journal, Bind 20, Nr. 43, 2014, s. 13976-13983.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

TY - JOUR

T1 - Robust Inclusion Complexes of Crown Ether Fused Tetrathiafulvalenes with Li+@C-60 to Afford Efficient Photodriven Charge Separation

AU - Supur, M.

AU - Kawashima, Y.

AU - Larsen, K. R.

AU - Ohkubo, K.

AU - Jeppesen, J. O.

AU - Fukuzumi, S.

PY - 2014

Y1 - 2014

N2 - Inclusion complexes of benzo-and dithiabenzocrown ether functionalized monopyrrolotetrathiafulvalene (MPTTF) molecules were formed with Li+@C-60 (1 center dot Li+@C-60 and 2 center dot Li+@C-60). The strong complexation has been quantified by high binding constants that exceed 10(6) (-1)(M) obtained by UV/Vis titrations in benzonitrile (PhCN) at room temperature. On the basis of DFT studies at the B3LYP/6-311G(d,p) level, the orbital interactions between the crown ether moieties and the p surface of the fullerene together with the endohedral Li+ have a crucial role in robust complex formation. Interestingly, complexation of Li+@C-60 with crown ethers accelerates the intersystem crossing upon photoexcitation of the complex, thereby yielding 3(Li+@C-60)*, when no charge separation by means of 1Li(+)@C-60* occurs. Photoinduced charge separation by means of 3Li(+)@C-60* with lifetimes of 135 and 120 ms for 1 center dot Li+@C-60 and 2 center dot Li+@C-60, respectively, and quantum yields of 0.82 in PhCN have been observed by utilizing time-resolved transient absorption spectroscopy and then confirmed by electron paramagnetic resonance measurements at 4 K. The difference in crown ether structures affects the binding constant and the rates of photoinduced electron-transfer events in the corresponding complex.

AB - Inclusion complexes of benzo-and dithiabenzocrown ether functionalized monopyrrolotetrathiafulvalene (MPTTF) molecules were formed with Li+@C-60 (1 center dot Li+@C-60 and 2 center dot Li+@C-60). The strong complexation has been quantified by high binding constants that exceed 10(6) (-1)(M) obtained by UV/Vis titrations in benzonitrile (PhCN) at room temperature. On the basis of DFT studies at the B3LYP/6-311G(d,p) level, the orbital interactions between the crown ether moieties and the p surface of the fullerene together with the endohedral Li+ have a crucial role in robust complex formation. Interestingly, complexation of Li+@C-60 with crown ethers accelerates the intersystem crossing upon photoexcitation of the complex, thereby yielding 3(Li+@C-60)*, when no charge separation by means of 1Li(+)@C-60* occurs. Photoinduced charge separation by means of 3Li(+)@C-60* with lifetimes of 135 and 120 ms for 1 center dot Li+@C-60 and 2 center dot Li+@C-60, respectively, and quantum yields of 0.82 in PhCN have been observed by utilizing time-resolved transient absorption spectroscopy and then confirmed by electron paramagnetic resonance measurements at 4 K. The difference in crown ether structures affects the binding constant and the rates of photoinduced electron-transfer events in the corresponding complex.

U2 - 10.1002/chem.201402449

DO - 10.1002/chem.201402449

M3 - Journal article

C2 - 25213225

VL - 20

SP - 13976

EP - 13983

JO - Chemistry: A European Journal

JF - Chemistry: A European Journal

SN - 0947-6539

IS - 43

ER -