Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1063-7834
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract This paper reports an investigation into the features of geminate recombination of long-lived electron-hole pairs in films of poly(N-epoxypropylcarbazole) (PEPC) containing intramolecular charge transfer compounds as centers of photogeneration of charge carriers carried out by measuring the attenuation kinetics of isothermal recombination luminescence over a wide range of temperatures (4.2–300 K) for times t〉1 s, along with the kinetics of photoinduced EPR signals. A study is made of how the presence of a potential barrier to the reverse transition of carriers to the recombination center and the initial triplet state of the charged pairs affects the geminate recombination. It is established that the kinetics of isothermal recombintation luminescence attenuation follow the law I(t)∝t −m for the times under study, where m takes values from 0.65 to 1.05. The first observations of a nonmonotonic change in m with temperature are reported (m passes through a minimum at a certain temperature), and a mechanism is proposed for recombination of charged pairs in PEPC containing intramolecular charge-transfer compounds as an explanation for this phenomenon.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1063-7834
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A nonexponential increase in photoconductivity with increasing temperature is discovered for poly(N-epoxypropylcarbazole) (PEPK) films doped with polymethine dyes. It is postulated that traps for nonequilibrium charge carriers form in these films during irradiation and are destroyed as the temperature is raised. Such traps are manifested by broadening of the high-temperature shoulder on the thermally stimulated luminescence (TSL) curves following the preliminary irradiation of PEPK films doped with polymethine and xanthene ionic dyes in the visible or UV range at 250–320 K and by the appearance of a new narrow TSL maximum near the preliminary irradiation temperature. These TSL features disappear after prolonged storage of the films in the dark or heating to higher temperatures.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Advanced Materials for Optics and Electronics 7 (1997), S. 99-103 
    ISSN: 1057-9257
    Keywords: amorphous molecular solids ; poly(N-epoxypropylcarbazole) ; thermoluminescence ; charge trapping ; charge transport ; energetic disorder ; dipole moments ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: The low-temperature thermoluminescence (TL) technique has been applied for probing the energetic disorder in doped poly(N-epoxypropylcarbazole)(PEPC) polymer films. Strong polar dopants were used for varying the degree of dipolar disorder. It was found that (1) the TL of the studied systems can be well interpreted in terms of the disorder model and (2) TL spectroscopy can provide the shape of the deepest part of the localised state distribution and the degree of energetic disorder as well. The charge trap distribution on the high-temperature side of the TL peak appears to be a Gaussian function and its halfwidth correlates well with the disorder parameter obtained from charge transport measurements. An unusual electric field effect on the TL of PEPC doped with strong polar dopants was found and is explained in terms of the contribution of the charge-dipole interaction to the energy of localised states. This effect indicates that the TL phenomenon for the studied systems cannot be explained purely by molecular γ-relaxation in the polymer. © 1997 John Wiley & Sons, Ltd.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...