Volume 83, Number 5, September 2008
Article Number 56001
Number of page(s) 5
Section Condensed Matter: Structural, Mechanical and Thermal Properties
Published online 20 August 2008
EPL, 83 (2008) 56001
DOI: 10.1209/0295-5075/83/56001

Origin of the anomalous X-ray diffraction in phthalocyanine films

Ge Liu1, T. Gredig1, 2 and I. K. Schuller1

1  Department of Physics, University of California - San Diego, La Jolla, CA 92093, USA
2  Department of Physics and Astronomy, California State University - Long Beach, CA 90840, USA

received 15 April 2008; accepted in final form 10 July 2008; published September 2008
published online 20 August 2008

The impact of the submolecular electron density on the X-ray diffraction profile of a layer-stacked thin film is studied experimentally and compared with numerical simulations based on the molecular structure and angular arrangement. Important structural information is contained in the X-ray diffraction profile of highly anisotropic molecular thin films, such as phthalocyanines. The results show that the intensity distribution of the diffraction peaks belonging to the same series of lattice planes provides important structural information including the molecular tilt angle and the center electron density of the molecule.

68.55.-a - Thin film structure and morphology.
68.37.-d - Microscopy of surfaces, interfaces, and thin films. - Solid surfaces and solid-solid interfaces: Structure and energetics: Polymers, organics.

© EPLA 2008