Heats of formation of transition-metal alloys: Full-potential approach and the Pt-Ti system
- Department of Physics, Brookhaven National Laboratory, Upton, New York 11973 (United States)
The heats of formation, {Delta}{ital H}, of the ordered phases of Pt-Ti are calculated using various approximations. This alloy system was chosen because of the availability of experimental data for {Delta}{ital H} for both high- and low-symmetry phases. The difference in the calculated heats of formation between a muffin-tin and a full-potential treatment can be substantial, as much as 0.25 eV/atom. While the total energies of the compounds and the reference elemental metals are all lowered (i.e., increased in binding), the change in {Delta}{ital H} depends on which energy is lowered more. For PtTi in the high-symmetry CsCl structure, {Delta}{ital H} is reduced, implying that the decrease of the total energy due to the full potential is larger for the elemental reference solids than for the compound. The calculated heats of formation are in accord with the experimental values and the known phase-diagram behavior, i.e., all the low-temperature phases predicted to occur as a function of composition are in fact observed.
- DOE Contract Number:
- AC02-76CH00016
- OSTI ID:
- 7238184
- Journal Information:
- Physical Review, B: Condensed Matter; (United States), Vol. 45:15; ISSN 0163-1829
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
PLATINUM ALLOYS
FORMATION HEAT
TITANIUM ALLOYS
TRANSITION ELEMENT ALLOYS
BETA-W LATTICES
BINDING ENERGY
MUFFIN-TIN POTENTIAL
PHASE DIAGRAMS
QUANTITY RATIO
SLATER METHOD
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0065-0273 K
ALLOYS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DIAGRAMS
ENERGY
ENTHALPY
PHYSICAL PROPERTIES
PLATINUM METAL ALLOYS
POTENTIALS
REACTION HEAT
TEMPERATURE RANGE
THERMODYNAMIC PROPERTIES
360104* - Metals & Alloys- Physical Properties