Internal structure constant for the primary star in the α CrB system in comparison to expectations from stellar structure models by Hejlesen (1987) and Claret (2019): green points and curve refer to the 2.5 M_⊙ model with (X = 0.7, Z = 0.0134) from Claret (2019); blue points and curve refer to the 2.51 M_⊙ model with (X = 0.7, Z = 0.02) from Hejlesen (1987); and red points and curve refer to the 2.51 M_⊙ model with (X = 0.7, Z = 0.04) from Hejlesen (1987). Black line indicates the inferred structure coefficient k₁ with an error estimate of 15%.