Molecular orientation of perfluoro-vanadyl-phthalo-cyanine examined by electron energy loss spectroscopy

A polymorph of perfluoro-vanadyl-phthalocyanine was found to be formed epit axially on a potassium iodide monocrystalline surface by vacuum deposition. The molecular orientation and molecular packing of the polymorph were anal ysed by a combination of several electron microscopic methods, namely elect ron diffraction, high-resolution imaging and electron energy loss spectrosc opy. The polymorph is different from the tetragonal polymorph previously ob tained on potassium chloride and potassium bromide single crystals. The mol ecular packing of the new polymorph on potassium iodide was found to be ort horhombic with a = 1.48 nm, b = 0.37 nm and c = 27 nm, the ab-plane being p arallel to the substrate surface. Copyright (C) 1999 John Wiley & Sons, Ltd .