Charge carrier mobility in quasi-one-dimensional systems: Application to a guanine stack

2003 ◽  
Vol 119 (11) ◽  
pp. 5690-5695 ◽  
Author(s):  
F. B. Beleznay ◽  
F. Bogár ◽  
J. Ladik
Keyword(s):  
Charge Carrier ◽  
Carrier Mobility ◽  
Charge Carrier Mobility ◽  
One Dimensional

Ultrafast Photoconductivity in Organic Semiconductors

2006 ◽  
Vol 935 ◽  
Author(s):  
Oksana Ostroverkhova ◽  
David G. Cooke ◽  
Frank A. Hegmann ◽  
John E. Anthony ◽  
Vitaly Podzorov ◽  
...  
Keyword(s):  
Charge Carrier ◽  
Organic Semiconductors ◽  
Carrier Mobility ◽  
Charge Carrier Mobility ◽  
Brick Wall ◽  
One Dimensional ◽  
Organic Molecular Crystals ◽  
Charge Carrier Dynamics ◽  
Transient Photoconductivity ◽  
Comprehensive Study

ABSTRACTWe present comprehensive study of ultrafast charge carrier dynamics in a variety of organic molecular crystals. In all samples, we observed sub-picosecond charge photogeneration and band-like transport, characterized by (i) an increase in charge carrier mobility as the temperature decreases in a wide temperature range of at least 20 K – 300 K and (ii) mobility anisotropy in the a-b plane of the crystals. The temperature dependence of the decay dynamics of the transient photoconductivity reveals the presence of shallow trapping sites in herring-bone-type-structured crystals (such as pentacene (Pc), tetracene (Tc), and rubrene (Rub)), while such traps are apparently absent in “brick-wall”-type crystals (such as functionalized pentacene (FPc)). We also report on the measurements of the charge carrier mobility anisotropy in the a-b plane of two types of FPc single crystals. Anisotropies of approximately 3.5 and 11.6 were obtained in the crystals characterized by crystal structures favoring two-dimensional and one-dimensional charge transport, respectively, consistent with the degree of π-overlap along different directions in the crystals.

Charge carrier mobility in one-dimensional aligned π-stacks of conjugated small molecules with a benzothiadiazole central unit

2017 ◽  
Vol 19 (12) ◽  
pp. 8330-8339 ◽  
Author(s):  
Deyan Raychev ◽  
Olga Guskova
Keyword(s):  
Charge Carrier ◽  
Small Molecules ◽  
Carrier Mobility ◽  
Charge Carrier Mobility ◽  
Charge Carriers ◽  
Central Unit ◽  
Dft Methods ◽  
Crystalline Materials ◽  
One Dimensional ◽  
Mobility Of Charge Carriers

The hopping mobility of charge carriers in organic crystalline materials consisting of benzothiadiazole-cored molecules with thiophene or furan flanks was analyzed using DFT methods.

The Influence of Nitrogen Position on Charge Carrier Mobility in Enantiopure Aza[6]helicene Crystals

2018 ◽  
Author(s):  
Francesco Salerno ◽  
Beth Rice ◽  
Julia Schmidt ◽  
Matthew J. Fuchter ◽  
Jenny Nelson ◽  
...  
Keyword(s):  
Solid State ◽  
Charge Carrier ◽  
Carrier Mobility ◽  
Chemical Structure ◽  
Crystal Packing ◽  
Charge Carrier Mobility ◽  
Individual Factor ◽  
Charge Mobility ◽  
Order Of Magnitude ◽  
Small Change

<p>The properties of an organic semiconductor are dependent on both the chemical structure of the molecule involved, and how it is arranged in the solid-state. It is challenging to extract the influence of each individual factor, as small changes in the molecular structure often dramatically change the crystal packing and hence solid-state structure. Here, we use calculations to explore the influence of the nitrogen position on the charge mobility of a chiral organic molecule when the crystal packing is kept constant. The transfer integrals for a series of enantiopure aza[6]helicene crystals sharing the same packing were analysed in order to identify the best supramolecular motifs to promote charge carrier mobility. The regioisomers considered differ only in the positioning of the nitrogen atom in the aromatic scaffold. The simulations showed that even this small change in the chemical structure has a strong effect on the charge transport in the crystal, leading to differences in charge mobility of up to one order of magnitude. Some aza[6]helicene isomers that were packed interlocked with each other showed high HOMO-HOMO integrals (up to 70 meV), whilst molecules arranged with translational symmetry generally afforded the highest LUMO-LUMO integrals (40 - 70 meV). As many of the results are not intuitively obvious, a computational approach provides additional insight into the design of new semiconducting organic materials.</p>

Sign in / Sign up

Export Citation Format

Share Document