Polarons in ladder-type polymer films: Recombination channels and electron-phonon coupling

Journal Article · Thu Apr 27 04:00:00 EDT 2000 · Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical

DOI:https://doi.org/10.1021/jp993370m· OSTI ID:20050850

Wohlgenannt, M; An, C P; Vardeny, Z V

The authors applied the photomodulation spectroscopy for probe-photon energies from 0.05 to 2.5 eV in films of ladder-type poly(p-phenylene) and identified a photoinduced absorption (PA) band related to triplet excitons and two correlated PA bands due to charged polarons. The low energy polaron band peaks at a relatively low photon energy of {approximately}0.1 eV, showing small polaronic relaxation energy. The authors employed photoinduced absorption-detected magnetic resonance spectroscopy to study the polaron recombination channels and found that spin {1/2} magnetic resonance enhances the bimolecular recombination of polarons to singlet byproducts (singlet excitons and bipolarons). However, it reduces polaron recombination to triplet byproducts, such as triplet excitons. The low-energy polaron PA shows antiresonances due to its overlap with Raman- and IR-active vibrations. The antiresonances program is compared to the IR and Raman spectra and found to also contain modes that are silent in the latter spectra.

• Research Organization: Univ. of Utah, Salt Lake City, UT (US)
• Sponsoring Organization: US Department of Energy; National Science Foundation
• DOE Contract Number: FG03-93ER45490
• OSTI ID: 20050850
• Journal Information: Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical, Journal Name: Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical Journal Issue: 16 Vol. 104; ISSN 1089-5647; ISSN JPCBFK
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ABSORPTION
ELECTRON-PHONON COUPLING
FILMS
MAGNETIC RESONANCE
POLARONS
POLYMERS