Dynamics of xenon, krypton, and methane monolayers in registry with graphite

Journal Article · Fri Jan 15 00:00:00 EST 1988 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.37.974· OSTI ID:5529599

Hakim, T M; Glyde, H R; Chui, S T

The self-consistent phonon (SCP) theory is used to study the dynamics of monolayers of xenon, krypton, and methane adsorbed on graphite. Only the ..sqrt..3 x ..sqrt..3 solid phase is considered. It is shown that the phonon energies of the Xe monolayers are very similar to those of their floating counterparts, while the interaction of the Kr and CH/sub 4/ monolayers with the graphite significantly affects the phonon dispersion curves. The gap in the phonon dispersion curves at the center of the Brillouin zone is computed as a function of temperature. At a critical temperature, the gap goes spontaneously to zero and a transition from a locked-in commensurate phase to a floating phase takes place. This transition appears to describe the commensurate to floating transition in CH/sub 4/ well. A simple model of the floating transition is compared to the full SCP calculations. The one-phonon dynamic form factor, including the cubic anharmonic term, and phonon lifetimes are also evaluated for Kr and CH/sub 4/.

• Research Organization: Department of Physics, University of Delaware, Newark, Delaware 19716
• OSTI ID: 5529599
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Vol. 37:2
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
GRAPHITE
SORPTIVE PROPERTIES
KRYPTON
ADSORPTION
PHONONS
METHANE
XENON
BRILLOUIN ZONES
DISPERSION RELATIONS
DYNAMICS
LAYERS
PHASE TRANSFORMATIONS
SELF-CONSISTENT FIELD
SOLIDS
SUBSTRATES
TEMPERATURE DEPENDENCE
ALKANES
CARBON
ELEMENTAL MINERALS
ELEMENTS
FLUIDS
GASES
HYDROCARBONS
MECHANICS
MINERALS
NONMETALS
ORGANIC COMPOUNDS
QUASI PARTICLES
RARE GASES
SORPTION
SURFACE PROPERTIES
ZONES
360603* - Materials- Properties
656002 - Condensed Matter Physics- General Techniques in Condensed Matter- (1987-)