Usage examples

configuration = MoleculeConfiguration(...)
scf = KohnShamMethod.apply(configuration)
molecular_spectrum = calculateMolecularEnergySpectrum(scf)
f = VNLFile("results.vnl")
f.addToSample(configuration,"my sample")
f.addToSample(molecular_spectrum,"my sample")

Print a formatted list of the eigenenergies. This function works for both spin-and unpolarized calculations:

def printSpectrum(spectrum):
    energies = spectrum.energies()
    if len(energies.shape)==2:
        # spin-polarized
        print '# Level\tSpin-Up (eV)\tSpin-Down (eV)'
        for i in range(energies.shape[1]):
            print "%i\t%g\t%g" % ( i,energies[0,i].inUnitsOf(eV),\
                energies[1,i].inUnitsOf(eV) )
    else:
        # not spin-polarized
        print '# Level\tEnergy (eV)'
        for i in range(len(energies)):
            print "%i\t%g" % ( i,energies[i].inUnitsOf(eV) )

Notes

The dimension of the list of energies returned by the method energies() depends on whether the performed SCF-calculation was spin-polarized. The shape property can be used to check whether the calculation was spin-polarized or not (as illustrated in the above script example).

The energy zero-level for the molecular spectrum is chosen at the vacuum level, i.e. the value of the effective potential far away from the molecule.

The molecular spectrum object can also be saved in a VNLFile for plotting in Virtual NanoLab, as also shown in the examples.

Use calculateEigenstateOccupations() to calculate the occupation of the eigenstates.

Further examples