Group hole mobility

Liquid Crystalline Systems. Conventional photoconductive polymers are amphorous or systems withlow order. In the case of PVK, the hole moves by hoppiag between the pendent carba2ole groups. The hole mobilities are usuaUylow, cm /Vs, due to a trap-dominated hoppiag... 

Electron or hole nature of the charge transfer may be realized in PVC-TNF Cl complexes depending on the concentration of the components [54]. The contribution of holes and electrons in conductivity is equal at the PVC-TNF ratio 1 1. Gill s experimental data for mobilities is shown in Fig. 10. The sharp concentration decrease of the neutral, noncoupled complex carbazole groups, leads to the fast decrease of the hole mobility. The electron mobility increase with increase of the TNF content was also accompanied by an increase of the... 

Poly silanes have a quantum efficiency of >30% and show a hole mobility of 10-4 cm2s-1V-1 at room temperature, independent of the side groups.37,38 Due to sufficient hole mobility, polysilanes are considered to be suitable materials for the hole-transporting layer in injection-type organic EL diodes.36 It is also known that polysilanes themselves can be efficient emission materials in the UV and visible regions. 

Hole mobilities of TAPC doped PC and PS were measured by Borsenberger and Bdssler (1991). For 75% TAPC, the data show a 100-fold increase in mobility when the PC is replaced with PS. For TAPC doped PS, n0 = 0.23 cm2/Vs, ct = 0.077 eV, and = 2.1. The corresponding values for TAPC doped PC are 2.0 x 10-2 cm2/Vs, 0.095 eV, and 3.1. The authors attributed the increase in mobility for TAPC doped PS to the elimination of random dipole Helds associated with the carbonyl groups of the PC and improved intermolecular coupling. 

Borsenberger (1992a) measured the concentration dependence of the hole mobility of TAPC doped PC. The width of the DOS increased with decreasing concentration, as illustrated in Fig. 31. The concentration dependence was attributed to dipole moments of the carbonyl groups. The concentration dependence of was attributed to packing constraints. From a plot of l°g(/ 0/p2) - 14.59 versus p, the wavefunction decay constant was determined... 

Abkowitz and Stolka (1990, 1991) compared hole mobilities of poly-silylanes and polygermylenes containing aliphatic pendants with compounds that contain only aromatic side groups. While transport occurred via states associated with the backbone chain in both compounds, the nature of the side groups was shown to influence the temperature dependence of the mobility. The results were described by a small-polaron argument, based on the assumption that the polarizability increases when an aromatic pendant group was substituted... 

Schnorer et al. (1988) measured hole mobilities of polysiloxane with pendant carbazole groups separated by three methylene units from the backbone. At 2.0 x 10 V/cm, the mobility decreased from 9.8 to 2.4 x 10-7 cm2/Vs as the thickness increased from 3 to 40 pm. The results were described by the Scher-... 

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