Theory of subsurface occupation, ordered structures, and order-disorder transitions for hydrogen on Pd(111)

Journal Article · Sun Feb 15 04:00:00 EST 1987 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.35.2128· OSTI ID:6974954

Daw, M S; Foiles, S M

The embedded-atom method (EAM) is applied to the calculation of the structure and phase diagram of H/Pd(111). Many-atom interactions are included inherently in the EAM, leading to substrate-mediated adatom interactions. The EAM predicts the occupation of both surface and subsurface sites forming two (..sqrt..3 x ..sqrt..3 )R30/sup 0/ structures at coverages of CTHETA = (1/3) and (2/3) monolayers. Zero-point energy corrections to the classical energies are required. In addition, the EAM is combined with Monte Carlo simulations to predict the critical temperatures of the order-disorder transformation. The symmetries of the predicted structures agree with the experimental low-energy electron diffraction patterns. The predicted critical temperatures of 120 and 110 K at CTHETA = (1/3) and (2/3) monolayers, respectively, are in excellent agreement with the experimental values of 85 and 105 K.

• Research Organization: Sandia National Laboratories, P.O. Box 969, Livermore, California 94550
• OSTI ID: 6974954
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 35:5; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ADSORPTION
COHERENT SCATTERING
CRITICAL TEMPERATURE
DIAGRAMS
DIFFRACTION
ELECTRON DIFFRACTION
ELEMENTS
HYDROGEN
MANY-BODY PROBLEM
METALS
MONTE CARLO METHOD
NONMETALS
ORDER-DISORDER TRANSFORMATIONS
PALLADIUM
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
PLATINUM METALS
SCATTERING
SIMULATION
SORPTION
SORPTIVE PROPERTIES
SURFACE PROPERTIES
SURFACES
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENTS
TRANSITION TEMPERATURE