Discrete dissociation model of photogenerated inter-chain charge transfer states in external electric field

0490818 - ÚMCH 2019 RIV SK eng J - Journal Article
Jex, M. - Menšík, Miroslav - Toman, Petr - Pfleger, Jiří
Discrete dissociation model of photogenerated inter-chain charge transfer states in external electric field.
Chemical Papers. Roč. 72, č. 7 (2018), s. 1707-1718. ISSN 0366-6352
R&D Projects: GA MŠMT(CZ) LTC17029; GA ČR(CZ) GA15-05095S; GA ČR(CZ) GA17-03984S
EU Projects: European Commission(XE) MPNS COST Action MP1406
Institutional support: RVO:61389013
Keywords : pi-conjugated polymers * charge carrier photogeneration * photoconductivity
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 1.246, year: 2018

A new theoretical model of photogeneration yield of free charge carriers on the electric field in π-conjugated polymers was introduced. It generalizes the model of Arkhipov et al. (Chem Phys Lett 372:886–892, 2003a) where the dissociation of the inter-chain charge transfer states is controlled by a thermally activated transition from the lowest quantum state over a potential barrier. Contrary to the previous model based on the effective mass approximation, the new model determines the potential and transfer integrals between HOMO orbitals, using quantum chemical methods. The model successfully explained experimental dependences of photogenerated charge yield in poly{1-[4-(trimethylsilyl)phenyl]-2-phenylacetylene} exhibiting a strong sensitivity on electric field strength over a very large interval. This indicates the model applicability for estimation of fill factor in solar cells. The model was found stable toward various distributions of charge transfer states (on-chain delocalization, charge transfer to side groups, helix structure, etc.) and tunneling effects behind potential barrier.
Permanent Link: http://hdl.handle.net/11104/0284961