HIGH-RESOLUTION X-RAY-DIFFRACTION STUDIES ON HEXAPHENYL THIN-FILMS

The direction of the preferred growth of hexaphenyl crystallites withi n thin films can be adjusted by varying the sample preparation conditi ons. Two types of samples with different preferred growth are investig ated by Theta/2 Theta scans at different tilt angles psi, the preferre d growth are characterised by either (00l) or (22-3) planes of hexaphe nyl crystallites parallel to the surface of the substrate. In both typ es of preferred growth the crystallites are highly ordered, the misali gnment of the (001) and (22-3) planes relative to the surface of the s ubstrate is within a few degrees. The two types of preferred growth ar e explained by layer growth of hexaphenyl molecules, the layers are pa rallel to the surface of the substrate. (C) 1998 Elsevier Science B.V. All rights reserved.