Fig. 2: The segregation energies of dopants in pristine Σ13 M(Al) GB.
From: Grain boundary structural transformation induced by co-segregation of aliovalent dopants

a The relaxed atomic structure model overlaid on ABF-STEM image viewed along the \([11\bar{2}0]\) axis, where Al and O atoms are represented by the colors of cyan and dark red, respectively. The arrowheads correspond to the center of the GB core. The dashed line indicates the GB position. The scale bar is 2 Å. The segregation energies of b Ca and c Si atoms at respective atomic sites in the pristine Σ13 M(Al) GB structure, where the color indicates the segregation energy in eV. d The segregation energies of Ca (green), Si (red), and Si with a Ca at A site (white with a dark red edge) as a function of projected distance from the GB plane of (\(10\bar{1}4\)). The labels of respective atomic sites (A – I) is given in b. e The Voronoi volumes (Å3) at respective cation sites in the structure model of Σ13 M(Al) GB.