X-ray diffraction is a well established and powerful technique for studying texture (and hence molecular orientation) in crystalline materials, but it cannot provide any information about amorphous or nanocrystalline films. In electron paramagnetic resonance (EPR) spectroscopy the signal comes from the spin of unpaired electrons in the material. This technique therefore does not require the sample to be crystalline. It works for any sample with paramagnetic centres such as the MPcs where the unpaired electrons are contributed by the metal. In this paper we present a continuous-wave X-band EPR study using the anisotropy of the EPR spectrum of CuPc  to determine the orientation effects in different types of CuPc films. From these measurements we gain insight into the molecular arrangement of films with different spin concentrations, and apply our technique to the study of molecular orientation in photovoltaic cells.
|Publication status||Published - Aug 2010|
|Event||3rd Topical Meeting on Spins in Organic Semiconductors (SpinOSIII) - Amsterdam, Netherlands|
Duration: 31 Aug 2010 → 03 Sep 2010
|Conference||3rd Topical Meeting on Spins in Organic Semiconductors (SpinOSIII)|
|Period||31/08/2010 → 03/09/2010|