Conformational fluctuations and large fluorescence spectral diffusion in conjugated polymer single chains at low temperatures
Pullerits, Tönu LU ; Mirzov, Oleg LU and Scheblykin, Ivan LU
(2005)
In The Journal of Physical Chemistry Part B
109(41).
p.19099-19107
- Abstract
- The fluorescence of single chains of the conductive polymer poly [2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV) was studied by means of single-molecule spectroscopy at 15 K. MEH-PPV was deposited onto a surface from a toluene solution and covered with a polymer cap layer of poly(vinyl alcohol) spin-coated from an aqueous solution for protection against air. Because MEH-PPV is insoluble in water, such sample preparation guarantees that MEH-PPV chains do not mix with the cap polymer. We found that this "host matrix free" environment results in substantially stronger fluorescence spectral diffusion than that observed for conjugated polymer single chains embedded into polymer matrices. The average spectral diffusion range... (More)
- The fluorescence of single chains of the conductive polymer poly [2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV) was studied by means of single-molecule spectroscopy at 15 K. MEH-PPV was deposited onto a surface from a toluene solution and covered with a polymer cap layer of poly(vinyl alcohol) spin-coated from an aqueous solution for protection against air. Because MEH-PPV is insoluble in water, such sample preparation guarantees that MEH-PPV chains do not mix with the cap polymer. We found that this "host matrix free" environment results in substantially stronger fluorescence spectral diffusion than that observed for conjugated polymer single chains embedded into polymer matrices. The average spectral diffusion range was 500 cm(-1), and the maximum registered value reached 1100 cm(-1), which is similar to 6 times larger than the values reported before. We analyzed spectral diffusion by observation of temporal evolution of the fluorescence intensity, the position of the maximum, and the width of fluorescence spectra. We propose that the transition energy shifts are caused by the differences of the London dispersive forces in slightly different polymer chain conformations. Such conformational changes are possible even at low temperatures because the MEH-PPV single chains in our samples have more freedom for fluctuations than in the usual "in host" arrangement. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/151812
- author
- Pullerits, Tönu
LU
; Mirzov, Oleg
LU
and Scheblykin, Ivan
LU
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- in
- The Journal of Physical Chemistry Part B
- volume
- 109
- issue
- 41
- pages
- 19099 - 19107
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000232612100011
- scopus:27544455390
- pmid:16853463
- ISSN
- 1520-5207
- DOI
- 10.1021/jp052189c
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Chemical Physics (S) (011001060)
- id
- 01c91ca3-67ba-4185-8afd-4cde717abf4a (old id 151812)
- date added to LUP
- 2016-04-01 15:55:23
- date last changed
- 2022-03-22 07:11:09
@article{01c91ca3-67ba-4185-8afd-4cde717abf4a,
abstract = {{The fluorescence of single chains of the conductive polymer poly [2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV) was studied by means of single-molecule spectroscopy at 15 K. MEH-PPV was deposited onto a surface from a toluene solution and covered with a polymer cap layer of poly(vinyl alcohol) spin-coated from an aqueous solution for protection against air. Because MEH-PPV is insoluble in water, such sample preparation guarantees that MEH-PPV chains do not mix with the cap polymer. We found that this "host matrix free" environment results in substantially stronger fluorescence spectral diffusion than that observed for conjugated polymer single chains embedded into polymer matrices. The average spectral diffusion range was 500 cm(-1), and the maximum registered value reached 1100 cm(-1), which is similar to 6 times larger than the values reported before. We analyzed spectral diffusion by observation of temporal evolution of the fluorescence intensity, the position of the maximum, and the width of fluorescence spectra. We propose that the transition energy shifts are caused by the differences of the London dispersive forces in slightly different polymer chain conformations. Such conformational changes are possible even at low temperatures because the MEH-PPV single chains in our samples have more freedom for fluctuations than in the usual "in host" arrangement.}},
author = {{Pullerits, Tönu and Mirzov, Oleg and Scheblykin, Ivan}},
issn = {{1520-5207}},
language = {{eng}},
number = {{41}},
pages = {{19099--19107}},
publisher = {{The American Chemical Society (ACS)}},
series = {{The Journal of Physical Chemistry Part B}},
title = {{Conformational fluctuations and large fluorescence spectral diffusion in conjugated polymer single chains at low temperatures}},
url = {{http://dx.doi.org/10.1021/jp052189c}},
doi = {{10.1021/jp052189c}},
volume = {{109}},
year = {{2005}},
}