The natural logarithm of heating rate, ln ϕ, is plotted against 1000/T_g for (a) As₂S₃ and (b) As₂Se₃. The black dashed lines are the results of linear fitting, and the slope of the fitted line is − E a / R . Green triangle and purple diamond in Fig. 3(a) represent the As₂S₃ data from Espeau et al.,^[15] and Street and Yoffe.^[16] Orange triangle and olive diamond in Fig. 3(b) represent the As₂Se₃ data from Blachnik and Hoppe,^[17] and Chen et al.^[18]