Simulation of STM Pictures

To generate a STM image of a surface, two calculations need to be done, both using the same geometry, preferrentially a surface slab.

** 1.** Single point calculation of the structure of interest. Both a CHGCAR and a WAVECAR file need to be obtained. For this, activate the printout of both files:

• LCHARG = .TRUE. Activate printout of CHGCAR.
• LWAVE = .TRUE. Activate printout of WAVECAR. 2. Calculate the partial charge density which serves as template for simulating the STM picture. Copy the calculated CHGCAR and WAVECAR files to the folder and add the following keywords to the INCAR file:
• LPARD = .TRUE: Evaluate partial charge density.
• ISTART = 1 Read in the existent WAVECAR file.
• NBMOD = -3 Calculate partial charge density in an energy range given by EINT.
• EINT = [value1] [value2] The energy range for the partial charge density. Usually, [value1] should be set to the negative of the reported experimental STM current to compare with (e.g., -1 for 1 eV current), [value2] should be zero.