# CP2K XPS

## Pt 4f

System info:
- Pt, FCC
- bulk, supercell 3x3x3, cell size: 11.76
- number of atoms: 108

Replace one Pt atom by a new kind `Pt1`:

      &KIND Pt
         BASIS_SET DZVP-MOLOPT-SR-GTH-q18
         ELEMENT Pt
         POTENTIAL GTH-PBESOL-q18
      &END KIND
      &KIND Pt1
         BASIS_SET DZVP-MOLOPT-SR-GTH-q18
         CORE_CORRECTION 1
         ELEMENT Pt
         POTENTIAL GTH-PBESOL-q19_4f13
      &END KIND

Then I calculated the energy difference between two systems:

E_b = E_13 - E_14 = -421.14 (eV)

The binding energy of Pt 4f is 71.2 eV from experimental data.

### Singe atom test

I also tried to calculate the binding energy of a single Pt atom

E_b = E_13 - E_14 = -10.81 (eV)

In a calculation using Quantum ESPRESSO, the value is ~ 68 eV.