Left panels: abundance patterns as a function of T_c (Lodders 2003). The metal abundances of α Cen A and B relative to iron, [X/Fe], are shown in the top and middle panels, respectively. Bottom panel: abundance differences, Δ[X/Fe], between α Cen A and B. To guide the eye, a dashed line is drawn at Δ[X/Fe] = 0. The dotted line in the bottom panel indicates the mean difference, while the grey strip shows the corresponding 1σ uncertainties. The vertical lines in the bottom of each panel show the non-LTE corrections (non-LTE minus LTE). A horizontal tick at the bottom or top of the line indicates a negative or positive correction, respectively. Values lower than ~0.01 dex are shown with a dot. Right panels: same as left panels, but after correction for GCE. The solid lines are the best linear fits to the refractory elements (T_c > 900 K; Table 4). The elements not included in the fit (Na, Mn, Ni, and Ce) are shown as open circles. The dashed line shows the typical GCE-corrected relationship found for solar analogues (Bedell et al. 2018) after adjustment of the intercept to minimise the residuals.