Step 2. Set calculation options

Next we will set up the calculation. The following details need to be set:

Set the title to 'TlH spin-orbit coupled'.
Select the preset 'FragmentAnalysis' in the 'Preset' menu.
Select 'GGA:BP' from the 'xc potential in SCF' menu.
Select 'Spin-Orbit' from 'Level of relativistic theory' menu.
Select the basis set 'TZ2P' from the 'Basis Set' Menu.
Select the core type 'None' from the 'Core Type' menu.

The 'Main Options' Menu will now look like:

Note that we choose the Fragment Analysis preset. We will define the whole molecule as one fragment, and set its name for clarity:

Select both atoms
Press and hold the Right mouse button on one of the selected atoms
Select from the pop-up menu 'New Fragment ...'
Enter the name 'TlH_SR' in the 'Fragment name' field
Click 'OK'