Slow polymer dynamics in poly(3-hexylthiophene) probed by muon spin relaxation

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Takeshita, S., Hori, K., Hiraishi, M., Okabe, H., Koda, A., Kawaguchi, D., Tanaka, K., Kadono, R.
Format: Preprint
Veröffentlicht: 2024
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866911961674940416
author Takeshita, S.
Hori, K.
Hiraishi, M.
Okabe, H.
Koda, A.
Kawaguchi, D.
Tanaka, K.
Kadono, R.
author_facet Takeshita, S.
Hori, K.
Hiraishi, M.
Okabe, H.
Koda, A.
Kawaguchi, D.
Tanaka, K.
Kadono, R.
contents The molecular dynamics of regioregulated poly(3-hexylthiophene) P3HT is investigated using muon spin relaxation ($μ$SR). The response of the $μ$SR spectra to a longitudinal magnetic field ($B_{\rm LF}$, parallel to the initial muon spin direction) indicates that the implanted muons form both muonated radicals localized on the thiophene ring and diamagnetic states with comparable yields. Moreover, the unpaired electron in the radical undergoes hyperfine interactions with muon bound to thiophene and with neighboring protons, whose fluctuations can serve as a measure for the molecular dynamics. The $B_{\rm LF}$ dependence of the longitudinal muon spin relaxation rate ($1/T_{1μ}$) measured in detail at several temperatures is found to be well reproduced by the spectral density function $J(ω)$ derived from the local susceptibility that incorporates the Havriliak-Negami (H-N) function used in the analysis of dielectric relaxation, $χ(ω)\propto1/[1-i(ω/\tildeν)^δ]^γ$ (where $\tildeν$ is the mean fluctuation rate, and $0<γ, δ\le1$). The magnitude of $\tildeν$ and its temperature dependence deduced from the analysis of $1/T_{1μ}$ are found to be consistent with the motion of hexyl chains and thiophene rings suggested by $^{13}$C-NMR. The present result marks a methodological milestone in the application of $μ$SR to the dynamics of complex systems with coexisting fluctuations over a wide range of time scales, such as polymers.
format Preprint
id arxiv_https___arxiv_org_abs_2406_18952
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Slow polymer dynamics in poly(3-hexylthiophene) probed by muon spin relaxation
Takeshita, S.
Hori, K.
Hiraishi, M.
Okabe, H.
Koda, A.
Kawaguchi, D.
Tanaka, K.
Kadono, R.
Materials Science
Soft Condensed Matter
The molecular dynamics of regioregulated poly(3-hexylthiophene) P3HT is investigated using muon spin relaxation ($μ$SR). The response of the $μ$SR spectra to a longitudinal magnetic field ($B_{\rm LF}$, parallel to the initial muon spin direction) indicates that the implanted muons form both muonated radicals localized on the thiophene ring and diamagnetic states with comparable yields. Moreover, the unpaired electron in the radical undergoes hyperfine interactions with muon bound to thiophene and with neighboring protons, whose fluctuations can serve as a measure for the molecular dynamics. The $B_{\rm LF}$ dependence of the longitudinal muon spin relaxation rate ($1/T_{1μ}$) measured in detail at several temperatures is found to be well reproduced by the spectral density function $J(ω)$ derived from the local susceptibility that incorporates the Havriliak-Negami (H-N) function used in the analysis of dielectric relaxation, $χ(ω)\propto1/[1-i(ω/\tildeν)^δ]^γ$ (where $\tildeν$ is the mean fluctuation rate, and $0<γ, δ\le1$). The magnitude of $\tildeν$ and its temperature dependence deduced from the analysis of $1/T_{1μ}$ are found to be consistent with the motion of hexyl chains and thiophene rings suggested by $^{13}$C-NMR. The present result marks a methodological milestone in the application of $μ$SR to the dynamics of complex systems with coexisting fluctuations over a wide range of time scales, such as polymers.
title Slow polymer dynamics in poly(3-hexylthiophene) probed by muon spin relaxation
topic Materials Science
Soft Condensed Matter
url https://arxiv.org/abs/2406.18952