The Structures of C60 Films on Different Single-Crystal Substrates

✍ Scribed by Wei Zhao; Wei-Lie Zhou; Li-Quan Chen; Yu-Zhen Huang; Ze-Bo Zhang; K.K. Fung; Zhong-Xian Zhao

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 660 KB
• Volume: 112
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1994.1326

✦ Synopsis

The structures of (\mathrm{C}{60}) films sublimated on the ( 001 ) surface of five substrates, (\mathrm{LaAlO}{3}, \mathrm{SrTiO}{3}, \mathrm{ZrO}{2}, \mathrm{NaCl}), and (\mathrm{KBr}), and an amorphous quartz substrate were studied by XRD and TEM. All films are of fcc structure with corresponding lattice parameters (a=14.10,14.10,14.17,14.16,14.25), and (14.12 \AA), respectively. Various factors influencing the lattice constant are discussed. TEM was used to investigate two (\mathrm{C}{60}) films prepared on (\mathrm{NaCl}(001)) substrates with different temperatures and showed that in the initial growth stage of the film, it mainly contains microparticles with fcc structure; a few particles of hep structure with (a=1.02) and (b=1.64 \mathrm{~nm}) coexist in the film. With higher substrate temperature and growth of the film, the number of hcp phase particles was reduced. These results indicate that planar defects and hcp phase particles may contribute to the low-angle sawtooth feature on the (111) peak in the XRD patterns. The existence of an abnormal defect in fcc stacking with a sequence (A B C A A A A B C \ldots) in the 〈111) direction, which is normally impossible in fcc spherical packings, suggests that the adhesion forces between (\mathrm{C}{60}) molecules are strong to some extent. 1994 Academic Press. Inc.