Long Period Superlattice Cu3Au II

摘要: A detailed study of the Cu-Au system between 25–50 at. % Au was made to determine range stability long period superlattices found in this system. The single-crystal thin film technique used make samples, and structure determined using electron diffraction. It that a one-dimensional superlattice exists as an equilibrium phase from about 30% Au, substantiating Scott's original observation, 60% Au. From 38% antiphase is Cu3Au II type, while at higher content, CuAu type. domain size M decrease continuously value 10 5 50% regardless change when crossing region CuAu. Small amounts Al added sample having content 40%, decreased manner identical observed for stoichiometric II. addition 27.5%, where not observed, resulted formation which could be predicted by our present theory. Qualitative arguments are presented explain appearance these structures. Particular emphasis placed on role boundary energy determining superlattice.