Fig. 4: Calculated transition states for the C-H activation of methane at Pd(II).
From: The continuum of carbon–hydrogen (C–H) activation mechanisms and terminology

All energies are relative to sigma complex 2.1, Fig. 2. Pd-H red dashed lines in A and B do not represent an interaction, instead are representative of distance to the metal, whereas the dashed line in C does represent a Pd-H interaction.