Issue 27, 2020

Electron-donating strength dependent symmetry breaking charge transfer dynamics of quadrupolar molecules

Abstract

The excited state symmetry breaking charge transfer (SBCT) dynamics of two diacetylide-triphenylamine (DATPA) derivatives with different electron-donating abilities are investigated by femtosecond transient absorption and fluorescence spectroscopy. By tracking the evolution of the excited states by transient absorption spectra and the kinetics of the instantaneous emission dipole moments obtained from transient fluorescence spectroscopy, it is found that, in nonpolar solvent, the relaxed S1 state is quadrupolar with little change of emission dipole moments for the two molecules within 30 ps, whereas in polar solvent, the quadrupolar state evolves to a symmetry broken S1 state, in which, the emission dipole moment exhibits a fast reduction in the first few picoseconds. The larger reduction in emission transition dipole moment for the molecule with stronger electron-donating methoxy groups indicates a larger extent of symmetry breaking compared with the one with weak electron-donating methyl groups. Consequently, we revealed that the magnitude of symmetry breaking can be tuned by changing the electron-donors in quadrupolar molecules.

Graphical abstract: Electron-donating strength dependent symmetry breaking charge transfer dynamics of quadrupolar molecules

Supplementary files

Article information

Article type
Paper
Submitted
09 May 2020
Accepted
27 Jun 2020
First published
29 Jun 2020

Phys. Chem. Chem. Phys., 2020,22, 15743-15750

Electron-donating strength dependent symmetry breaking charge transfer dynamics of quadrupolar molecules

X. Niu, Z. Kuang, M. Planells, Y. Guo, N. Robertson and A. Xia, Phys. Chem. Chem. Phys., 2020, 22, 15743 DOI: 10.1039/D0CP02527E

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements