Isoelectronic Analogs of Pentaphene

The asymmetric compound 38 has a HOMO energy of -5.35 eV, which is smaller than that of 34 and similar to that of 4 [51]. This compound has a herringbone arrangement in the crystal and exhibits high hole mobility of up to 0.41 cm V s and ambient stability. Compound 39 with one more benzene ring has a HOMO energy of -5.11 eV and mobility of 0.13 cm V s [52]. On the other hand, the symmetric compound 40 has a it-stacking structure, and the mobility is relatively low ( 10 cm V s ) [53]. 

This series, which was mainly developed by Takimiya et al, is the most promising p-type organic semiconductors for use in practical applications at this time due 

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