Distribution rules of systematic absence and generalized de Wolff figure of merit applied to EBSD ab-initio indexing

Abstract

For EBSD ab-initio indexing, a new method that adopts several methods originally invented for powder indexing, is reported. Distribution rules of systematic absence and error-stable Bravais lattice determination are used to eliminate negative influence of non-visible bands and erroneous information from visible bands. In addition, generalized versions of the de Wolff figures of merit are proposed as a new sorting criterion for the obtained unit-cell parameters, which can be used in both orientation determination and ab-initio indexing from Kikuchi patterns. Computational results show that the new figures of merit work well, similarly to the original de Wolff $M_n$. Ambiguity of indexing solutions is also pointed out, which happens in particular for low-symmetric cells, and may generate multiple distinct solutions even if very accurate positions of band center lines and the projection center are given.