Ab initio calculations to determine the formation enthalpy of Cu3Au phases.

Ab initio calculations ascertain that the difference of formation enthalpy between order and disordered Cu3Au phases is at least 0.044 eV per atom. The calculations also suggest that the tetrahedral clustering configuration and its spatial distribution have drastic effect on the formation enthalpy of the disordered structure and that segregation of the Au atoms significantly lowers the formation enthalpy of the disordered phases. [ABSTRACT FROM AUTHOR]