Anomalous absorption spectra of highly oriented thin films of triphenothiaselenazine

X-ray diffraction and absorption spectra of evaporated thin films of triphenothiaselenazine (TPTS) have been studied at room temperature. The X-ray diffraction pattern of the 900 Å film of TPTS comprises harmonic lines assigned to the n00 (n=1, 2, 3, 4, 5, 6 and 7) reflections. TPTS molecules in this film orient highly and arrange along the a∗-axis perpendicular to a substrate. An anomalous absorption band at around 800 nm was found for the 900 Å film of TPTS with sharp diffraction lines of the seventh order. This may be due to the strong intermolecular interaction in the highly oriented film.