A simple way to incorporate a scalar relativistic treatment is to use scalar relativistic pseudopotentials which can be generated by ADPACK. The another way is to use fully relativistic j-dependent pseudopotentials and to switch off the keyword 'scf.SpinOrbit.Coupling' as follows:
scf.SpinOrbit.Coupling off # On|Off, default=offThen, the j-dependent pseudopotentials are automatically averaged with a weight of j-degeneracy when they are read by OpenMX, which corresponds to scalar relativistic pseudopotentials. So, once j-dependent pseudopotentials are generated, you can utilize the pseudopotentials for both the fully and scalar relativistic treatments. Thus, we recommend that you make a fully relativistic j-dependent pseudopotential rather than a scalar relativistic pseudopotential, when relativistic effects are taken into account. In fact, the calculation in Fig. 28(a) was performed using the same pseudopotential as in Fig. 28(b) with 'scf.SpinOrbit.Coupling=off'.