RELATIVISTIC {level} {formalism} {potential}
Level
May be None (this suppresses the key, and is equivalent to not using the key at all), Scalar (default: scalar relativistic effects), or SpinOrbit (using double group symmetry).
Formalism
Pauli (default) or ZORA (ZORA is recommended!)
Potential
SAPA (default) or Full. The Full option is obsolete. It is here mainly for historical reasons. The SAPA method is described in Ref.[50] for the BAND program. The same potential is used in the ADF program. One may think that the Full option gives extra accuracy. However, this is not the case, it only leads to extra CPU time and extra DISK space usage.
The key RELATIVISTIC instructs ADF to take relativistic effects into account. By default (omission of the key) this is suppressed. Recommendation use: Relativistic Scalar ZORA or Relativistic SpinOrbit ZORA.
Pauli
