Thermodynamics of ordered and disordered phases in the binary Mo-Ru system
2007 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 75, no 18, 184203- p.Article in journal (Refereed) Published
Wehave performed ab initio calculations of the mixing enthalpy forthe Mo-Ru alloy system. Both completely random alloys on thefcc, bcc, and hcp lattices as well as ordered andpartially ordered structures based on the hcp lattice and a phase have been examined. Further, we have performed aground-state search for the Ru-rich region using ab initio derivedeffective interactions, and find a series of structures below thetie line of the simple compounds. Using the structures fromthis ground-state search, we are able to make an estimationof the contribution to the total energy due to orderingeffects in this system. We find unusually large deviations betweencalculated and experimental values of the mixing enthalpy for Ru-richhcp alloys. Our calculations indicate, in agreement with experiment, thatthere are ordering trends in the system. However, even underassumption of maximal order theoretical results differ substantially from theexperiment. Possible reasons for the disagreement are discussed.
Place, publisher, year, edition, pages
2007. Vol. 75, no 18, 184203- p.
molybdenum alloys, ruthenium alloys, ab initio calculations, enthalpy, ground states, total energy
National CategoryEngineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-14273DOI: 10.1103/PhysRevB.75.184203OAI: oai:DiVA.org:liu-14273DiVA: diva2:23067