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...than merely the levels at the lower end of the band. In this case,sthe approximation behind the effective mass concept used in conventional band theory is no longer validsand the mobility is given by =-=[Zim64]-=-shh Ja kT eaJ kT e r ⋅=⋅= λτµ 02 22 0s(2.2)swhere τr, J, a, λsare a relaxation time, the intermolecular electron overlap integral, the lattice constant,sand the mean free path of the electron, respect...

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...ve been seen in the development of organic light emittingsdiodes (OLEDs). Currently, the highest observed luminous efficiencies of derivatives of these materialssexceed that of incandescent lighbulbs =-=[She96]-=-. The electronic and optical properties of these “active”sorganic materials are now suitable for low-performance, low cost electronic products that can address thesneeds for lightweight portable devic...

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...charge, or holes,swith positive charge. The upper limits in microscopic mobilities of organic molecular single crystals,sdetermined at 300 K by time-of-flight experiments, are between 1 and 10 cm2/Vs =-=[Wri95]-=-. The mobilitiessof organic molecular thin films are expected to be even smaller due to impurities, defects or grainsboundaries that exist in the films. The weak intermolecular interaction forces in o...