title: Crystal, molecular and electronic structure of N,N'-diphenyl-N,N'-bis(2,4-dimethylphenyl)-(1,1'-biphenyl)-4,4'-diamine and the corresponding radical cation.
abstract: Oxidation of N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD, 1 a) and N,N'-diphenyl-N,N'-bis(2,4-dimethylphenyl)-(1,1'-biphenyl)-4,4'-diamine (1 b) with SbCl(5) affords the corresponding radical cations quantitatively. The crystal and molecular structure of 1 b and [1 b]SbCl(6), the first tetraphenyl benzidene derivatives to be characterised crystallographically in both the neutral and radical cation states, reveal molecular parameters in agreement with the predictions made on the basis of DFT studies. Analysis of the NIR transition in the radical cations [1](+) (.) allows an estimate of the electronic coupling parameter V (1 a(+) (.) 3200 cm(-1); 1 b(+) (.) 3300 cm(-1)), the reorganisation energy lambda(1 a(+) (.) 7500 cm(-1); 1 b(+) (.) 7800 cm(-1)), and the linear coupling constant l (1 a(+) (.) 3100 cm(-1); 1 b(+) (.) 2700 cm(-1)) of the symmetric mode.
authors.affiliation: Department of Chemistry, University of Durham, South Road, Durham, DH1 3LE, UK. p.j.low@durham.ac.uk
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Low
authors.forename: Michael A J
authors.initials: MA
authors.lastname: Paterson
authors.forename: Horst
authors.initials: H
authors.lastname: Puschmann
authors.forename: Andrés E
authors.initials: AE
authors.lastname: Goeta
authors.forename: Judith A K
authors.initials: JA
authors.lastname: Howard
authors.forename: Christoph
authors.initials: C
authors.lastname: Lambert
authors.forename: Julian C
authors.initials: JC
authors.lastname: Cherryman
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Tackley
authors.forename: Stephen
authors.initials: S
authors.lastname: Leeming
authors.forename: Bev
authors.initials: B
authors.lastname: Brown