The angular-shaped n-type semiconductors 2-(12H-dibenzofluoren-12-ylidene)malononitrilediimide 2a and 2b were successfully designed, synthesized, and fully characterized by optical absorption and fluorescence, cyclic voltammetry, X-ray crystal structure analysis, XRD, and OFET device performance. The varying alkyl chain lengths of 2a and 2b caused different molecular orientations with respect to the substrate. Thus, 2a presents an electron mobility of 0.01 cm(2) V(-1) s(-1), whereas 2b resulted in poor device performance with a much lower electron mobility of 5 × 10(-4) cm(2) V(-1) s(-1).