Author Topic: To converge optical spectra  (Read 2767 times)

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Offline ams_nanolab

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To converge optical spectra
« on: June 21, 2016, 08:01 »
What's the rule of thumb to converge optical spectra w.r.t. the no. of bands to be included above and below the Fermi level? If I look for spectra in the range of 0-5 eV, so it should include all the bands within -2.5 eV to +2.5 eV ? But I have noticed if there are say 100 bands in the energy range and I go on increasing even more bands (say 200-300) the spectra still changes, although so many bands may not be even present in the said energy range. What am I missing?  ???

Offline Ulrik G. Vej-Hansen

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Re: To converge optical spectra
« Reply #1 on: June 21, 2016, 10:07 »
It depends somewhat on your system, but we have seen cases where it is necessary to go to more than 30 eV above the Fermi level. There is not a 1-to-1 correspondence between the energy of your photons and the energy range which is necessary to investigate.

Offline ams_nanolab

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Re: To converge optical spectra
« Reply #2 on: June 21, 2016, 11:55 »
Yes, that seems to be the case. Thanks  :)