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General Questions and Answers / About Energy dependent LDDOS

« on: May 30, 2014, 04:06 »

Dear everyone,
    In the picture of Energy dependent LDDOS, what do the numbers in the z axis mean? And in the calculating, how can I modify the parameters in the script below, such as “contour_values” and “pylab.axis”?

# import list with lddos
lddos_list = nlread('lddos.nc', LocalDeviceDensityOfStates)

#Find the z-spacing
dX, dY, dZ = lddos_list[0].volumeElement().convertTo(Ang)
dz = dZ.norm()
shape = lddos_list[0].shape()
z = dz * numpy.arange(shape[2])

# calculate average lddos along z for each spectrum
energies = []
lddos_z = []
for lddos in lddos_list:
    energies = energies + [lddos.energy().inUnitsOf(eV)]
    avg_z = numpy.apply_over_axes(numpy.mean,lddos[:,:,:],[0,1]).flatten()
    lddos_z = lddos_z + [avg_z]

# plot as contour plot
# make variables
energies = numpy.array(energies)
X, Y = numpy.meshgrid(z, energies)
Z = numpy.array(lddos_z).reshape(numpy.shape(X))


import pylab
#plot the LDDOS(E, z)
pylab.xlabel('z (Angstrom)',fontsize=12,family='sans-serif')
pylab.ylabel('Energy (eV)',fontsize=12,family='sans-serif')
contour_values = numpy.linspace(0,0.02,21)
pylab.contourf(X, Y, Z, contour_values)
pylab.colorbar()
pylab.axis([6,16,-3, 3])

pylab.title('Au-DTB-Au : LDDOS(E, z)')
pylab.savefig('lddos.png',dpi=100)


pylab.show()
pylab.title('Au-DTB-Au : LDDOS(E, z)')
pylab.savefig('lddos.png',dpi=100)