Without SOC, the Group 14 elements (C, Si, Ge and Sn) have a 3-fold spin degeneracy and a 3-fold spatial degeneracy in their 3 P ground state. The degeneracy is lifted by the SOC, resulting in the (green) functionals were adopted for SOC-MRSF. For comparison, the results of 4c-CASPT2 (dotted) and 4c-CASSCF (solid black line) using uncontracted cc-pVXZ (X = D, T, Q) were also shown.