Three-dimensional molecular packing of thin organic films of PTCDI-C8 determined by surface X-ray diffraction

Tobias N Krauss; Esther Barrena; Xue N Zhang; Dimas G de Oteyza; János Major; Volker Dehm; Frank Würthner; Leide P Cavalcanti; Helmut Dosch

doi:10.1021/la8030182

Three-dimensional molecular packing of thin organic films of PTCDI-C8 determined by surface X-ray diffraction

Langmuir. 2008 Nov 18;24(22):12742-4. doi: 10.1021/la8030182. Epub 2008 Oct 17.

Authors

Tobias N Krauss¹, Esther Barrena, Xue N Zhang, Dimas G de Oteyza, János Major, Volker Dehm, Frank Würthner, Leide P Cavalcanti, Helmut Dosch

Affiliation

¹ Max-Panck-Institut fur Metallforschung, Heisenbergstrasse, Stuttgart, Germany.

PMID: 18925759
DOI: 10.1021/la8030182

Abstract

We have determined the full molecular 3D packing of thin organic films of the archetypical organic n-type semiconductor N, N'-dioctyl-3,4:9,10-perylene tetracarboxylic diimide (PTCDI-C 8) by surface X-ray crystallography. We show that PTCDI-C 8 forms smooth layered films on Al 2O 3 (11-20) with an outstanding degree of molecular order. The thin-film structure is found to consist of a triclinic unit cell with the plane of the aromatic core tilted by 67 +/- 2 degrees with respect to the surface plane, which differs significantly from the bulk structure. The 3D crystallites extend with vertical coherent order across the entire film thickness.