Atomic nonaffinity as structural indicator of protocol-dependent plasticity in amorphous solids*

Structural heterogeneity of amorphous solids challenges the prediction of plastic events which is intimately connected to their mechanical behaviors. Here we report the atomic nonaffinity, as a structural indicator with intrinsic orientation, which is derived from the total nonaffine modulus based on a perturbation analysis of the potential energy landscape. We find that the atomic nonaffinity can efficiently characterize the locations of plastic events, which is comparable to other indicators. More importantly, it can accurately predict the protocol-dependent response of plastic events by quantitatively analyzing the relation between its softest direction and shear loading direction. These results shed light on the characterization and prediction of the mechanical response of amorphous solids.