In order to determine the evolution of the atomic structure through a glass transition, in situ synchrotron X-ray scattering measurements were performed as a function of temperature using a model material: Zr-Cu-Al metallic glass. Based upon the study of the pair distribution function and the characterization of the free volume in terms of atomic bonding lengths, it was found that the relative change of the quantity, ΔN/N (N representing the number of atom pairs), with significantly longer interatomic distances for the nearest atomic pairs, increased abruptly above the glass transition temperature. These phenomena were interpreted in terms of a tight-bond cluster model.

Atomic Migration and Bonding Characteristics during a Glass Transition Investigated using As-Cast Zr-Cu-Al. C.Fan, Y.Ren, C.T.Liu, P.K.Liaw, H.G.Yan, T.Egami: Physical Review B, 2011, 83[19], 195207