# Example: ZORA Relativistic Effects: Au2¶

Download Au2_ZORA.run

A relativistic geometry optimization with the ZORA formalism. Both a scalar relativistic geometry optimization, as well as a spin-orbit coupled relativistic geometry optimization are performed. Spin-orbit effects on the geometry are often not so large for closed shell molecules, but takes typically a factor 4 times as much as a scalar relativistic calculation.

The input for the spin-orbit coupled relativistic geometry optimization is given below. The only difference between this input and the input for the scalar relativistic geometry optimization is the key RELATIVISTIC. Use ‘Relativistic scalar ZORA’ in case of scalar relativistic ZORA calculations.

\$ADFBIN/adf << eor
Title  Au2  relativistic optimization: spinorbit ZORA

Integration  5 5

Atoms  Zmat
Au   0 0 0
Au   1 0 0  2.5
End

Basis
Type TZ2P
Core Small
End

Relativistic SpinOrbit ZORA

Geometry