Impact of substitution on the reorganization energy of bis-triarylamine derivatives

The impact of substitution on the reorganization energy (λ) of N,N′-diphenyl-N,N′-bis (3-methyllphenyl)-(1,1′-biphenyl)-4,4′-diamine (TPD) derivatives (TPDs) is evaluated from the results of quantum-mechanical calculations performed at density functional theory levels. In this article, models modified on the central biphenyl and on the side phenyl are designed. The relationship between reorganization energy and substitution is analyzed and qualitatively established. These results help us to design material for OLED with desirable hole carrier transport properties.