Contrasting the Building Blocks of Grain Boundaries using Local vs. Multi-Scale Universal Descriptors

The behavior and properties of Grain Boundary (GB) Systems arise from a myriad of atomistic interactions. Is it possible to describe the properties of any GB in the system using knowledge of only a few? If so, which GBs have these essential, atomistic "building blocks" from which all other GB properties can be predicted? Previously, a universal similarity metric for GBs based on the Smooth Overlap of Atomic Positions (SOAP) descriptor was shown to effectively discover the underlying physics of GBs and find these atomistic building blocks. We present another universal GB representation using a multi-scale, scattering transform that also discovers GB building blocks. We contrast the building blocks discovered by SOAP with those of scattering transform to show the merits of local vs. multi-scale universal descriptors in describing the physics of GB.