Electron Diffraction and Imaging of Uncompressed Monolayers of Amphiphilic Molecules on Vitreous and Hexagonal Ice
J. Majewski 1,
L. Margulis 1,
D. Jacquemain 1,
F. Leveiller 1,
C. Bohm 2,
T. Arad 3,
Y. Talmon 4,
M. Lahav 1, and
L. Leiserowitz 1
1 Department of Materials and Interfaces, The Weizmann Institute of Science, 76100 Rehovot, Israel
2 Institut für Physikalische Chemie, Johannes Gutenberg Universität, D-6500 Mainz, Germany
3 Department of Structural Biology, The Weizmann Institute of Science, 76100 Rehovot, Israel
4 Department of Chemical Engineering, Technion-lsrael Institute of Technology, Haifa 32000, Israel
A new approach is described for probing domains of ordered self-assemblies of amphiphilic monolayers at the aqueous solution interface. The method has potential importance for the study of membrane structure, Langmuir-Blodgett films, and nucleation processes of two-and three-dimensional crystals. Electron diffraction (ED) patterns indicative of two-dimensional crystalline self-assembly were obtained from samples, which were examined by cryo-electron microscopy, of monolayers of water-insoluble amphiphiles on vitrified aqueour substrates. The apparent hexagonal symmetry of an ED pattern from a C16H33OH monolayer was interpreted in terms of multiple twinning. Monolayers of the CL31H63OH and cadmium salt of C19H39CO2H that were studied by dark-field techniques displayed faceted two-dimensional crystallites with a maximal size of 1 to 2 micrometers. Epitaxial nucleation of hexagonal ice by the C31H63OH monolayer has also been demonstrated by ED.
Submitted on March 16, 1993
Accepted on June 23, 1993