Related Experiment Video
Updated: Aug 9, 2026
Preparation of Carbon Nanosheets at Room Temperature
Published on: March 8, 2016
Theory of hexagonal and stripe phases in monolayers
1Department of Chemistry, Stauffer Laboratory of Physical Chemistry, Stanford University, Stanford, CA 94305.
Abstract:
Epifluorescence microscopy can be used to visualize the shapes of solid lipid domains in two-phase regions of monolayers at the air-water interface. The shapes of certain lipid domains result from a competition between a one-dimensional line tension and long-range intermolecular electrostatic repulsion. Under specified conditions, a finite two-dimensional domain with one shape can undergo a sharp transition to a second shape, as the area of the domain is changed. Two-dimensional infinite arrays of domains can also have transitions involving changes in the shapes and patterns of domains, such as the stripe to hexagonal phase transition [Andelman, D., Brochard, F. & Joanny, J. F. (1987) J. Chem. Phys. 86, 3673-3681]. The present paper treats the hexagonal and stripe phases with the same approximations and methods of calculation as used previously for the isolated, finite domains. It is shown that one effect of electrostatic repulsion between domains is to cause these domains to increase in size as they approach one another on monolayer compression. It is also shown that there can be two distinct conditions where the hexagonal and stripe phases coexist.
Related Concept Videos
02:37Metallic Solids
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
02:40MO Theory and Covalent Bonding
02:11Conformations of Cyclohexane
The chair form is the most stable and derives its name from its resemblance to the “easy chair.” In the chair conformation, two carbon atoms are arranged out-of-plane — one above and one below, minimizing the torsional strain. In the chair form, the bond angle is very close to the ideal tetrahedral value,...
01:28Phase Diagrams of Ternary Systems
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...