Three novel soluble acene derivatives consisting of the same functional group but varying in backbone size were characterized for their structural and electrical properties. An increase in acene length was found to directly contribute to more favourable packing schemes for hole transport, leading to field-effect mobilities of 1.8 cm(2)V(-1)s(-1) for difluoro tri-sec-butylsilylethynyl pentacenedithiophene, the longest derivative.