PHASESHIFTS

The PHASESHIFTS file is generated automatically with the eeasisss script during initialization if needed. If a PHASESHIFTS file is already present, a consistency check will be performed for the following features:

  • The energy range in the PHASESHIFTS file must be at least as large as the energy range to be calculated (THEO_ENERGIES)

  • The number of blocks per energy must either match the number of chemical elements (i.e. elements in POSCAR plus potentially elements added by ELEMENT_MIX), or the number of distinct sites (see SITE_DEF) times the number of elements that can occupy any given site (i.e. the format generated automatically, see below).

  • If the real part of the inner potentially is not defined explicitly, then the first line in the PHASESHIFTS file should contain the parameters defining that potential (see V0_REAL)

Format

The format of the PHASESHIFTS file is as follows:

The first line contains the number of blocks per energy, and four parameters for the real part of the inner potential, and an optional timestamp.

The data below is listed by energy, where the energy is given as a single floating-point value before the phase shifts for that energy. Energies are given in Hartree.

For each energy, there is one block per site and element occupying that site, where sites are defined by SITE_DEF and elements are at least the elements from the POSCAR file, with additional entries if elements were added via the ELEMENT_MIX parameter.

In each such block, there is one floating point value per angular momentum number \(L\), representing the phase shift that an electron with that \(L\) experiences when it scatters at the given site, occupied by the given element, at the given energy.

Example

Below, you find an example of what a PHASESHIFTS file may look like. The shown file is generated as part of the Ir(100)-O example. It has of three block for elements (O_surf, Ir_surf, Ir_def), each with phase shifts for angular momentum quantum number 0 through 17. Note, that the phase shifts for a single element may be split across two lines as is the case here.

3   -11.89   -0.15  -88.82   17.74      Ir(100)-O_example 221130-104323
0.5512
1.4793-1.0892 0.0178 0.0006 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
-0.7672-0.3853-0.9502 0.0147 0.0007 0.0000 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
-0.7517-0.3790-0.9060 0.0152 0.0007 0.0000 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
0.6615
1.3761-1.0791 0.0266 0.0010 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
-0.8554-0.4496-0.8502 0.0263 0.0014 0.0001 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
-0.8396-0.4421-0.8243 0.0271 0.0014 0.0001 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
0.7717
1.2832-1.0943 0.0360 0.0015 0.0001 0.0000 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
-0.9590-0.5219-0.8529 0.0406 0.0024 0.0001 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
-0.9430-0.5132-0.8329 0.0421 0.0025 0.0001 0.0000 0.0000 0.0000 0.0000
0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000
0.8820
...