Effect of Electronic States of Triphenylamine Derivatives on Their Charge Transport Properties

Abstract

Using the Dirac theory of constraints, the reduction procedure for the field degrees of freedom, the number of which is restricted by the equations of motion and topological conditions, is proposed. Such a procedure is applied to the Chern-Simons gravity generalized by the inclusion of a source, in the case when the space has a torus topology. The splitting of the discrete levels of time due to the presence of additional interaction is observed.

Towards an understanding of structure–property relationships in hole-transport materials: The influence of molecular conformation on oxidation potential in poly(aryl)amines

“…It seems that in 5a and 5b the C(19) methyl group, which hinders rotation about the N(1)-C(4) bond and restricts conjugation of the nitrogen lone pairs through the biphenyl moiety, necessitates a greater thermodynamic driving force for oxidation than is the case in the unrestricted systems 1, 3 and 4. The trend in E 1/2 (2) values is more keeping with the expected inductive effects (e.g. E 1/2 (2) 5b , 3), further supporting the hypothesis that upon oxidation the peripheral aromatic systems adopt an orientation more orthogonal to the central biphenyl group and are therefore less affected by the steric influence of the C(19) methyl group.…”

“…N,N,N9,N9-Tetraphenyl-1,19-phenyl-4,49-diamine (2). Diphenylamine (0.916 g, 5.43 mmol), diiodobiphenyl (1.0 g, 2.46 mmol), K 2 CO 3 (2.72 g, 19.68 mmol), copper powder (0.34 g, 5.3 mmol) and 18-crown-6 (0.13 g, 0.49 mmol) were dissolved in ortho-dichlorobenzene (10 ml) and heated at reflux for 18.5 h. The crude reaction mixture was diluted with MeOH to precipitate the crude product which was collected, dried and recrystallised from CH 2 Cl 2 to afford the pure title compound (0.68 g, 56%).…”

“…Several authors have used computational methods to address the structure-property issues in TPD-derived molecular materials, with particular emphasis on the geometric and electronic changes which accompany oxidation/hole transport phenomena. [1][2][3][4][5][6][7] In the case of N,N,N9,N9-tetra(aryl)-1,19biphenyl-4,49-diamines, which form one of the most widely employed classes of hole transport material the key conformational parameters (Fig. 1) can be considered to be: the torsion angle between the ring systems of the biphenyl moiety, i.e.…”

Improvement in Hole-Transport Property of Fullerene Materials by Hydrogenation: A Density Functional Theory Study on Fullerene Hydride C60H4

“…Kitamura and Yokoyama 23) reported that the uniformity of the positive charge distribution leads to the high mobility k ht in several hydrazone compounds. In contrast, Aratani et al 24) found that when HOMO distribution is localized on triphenylamine part of triphenylamine derivatives, the mobility k ht increase. Recently, Lin et al 25) theoretically reported that in the hole conduction is determined mainly by the moiety which contributes predominantly to its HOMO.…”

“…Up to now, however, many researchers [23][24][25] have reported the relationship between the HOMO and (or k ht ). Kitamura and Yokoyama 23) reported that the uniformity of the positive charge distribution leads to the high mobility k ht in several hydrazone compounds.…”