Step 2. Set calculation options and make fragment

Select 'Relativity' from the 'Model' Menu.
Select 'Spin-Orbit' from 'Level of relativistic theory' menu.

Select 'XC Functional' from the 'Model' Menu.
Select 'GGA-BP' from the 'xc potential in SCF' menu.

Select 'Main Options' from the Menu on the right hand side.
Enter the name 'TlH spin-orbit coupled' in the 'Title' Menu'.
Select the basis set 'TZ2P' from the 'Basis Set' Menu.
Select the core type 'None' from the 'Core Type' menu.
Select the preset 'FragmentAnalysis' in the 'Preset' menu.
Select both atoms.
Press and hold the Right mouse button on one of the selected atoms
  and select from the pop-up menu 'New Fragment ...'.
Enter the name 'TlH_SR' in the 'Fragment name' field.

The 'Main Options' Menu will now look like: