Mobility calculation for small band gap semiconductor

[umklapp]

Dear all,
To calculate the carrier mobility for small band gap semiconductors with free carriers (1E20), I tried a few scissor-shifts to increase the gap. However, I am always getting the following errors, for example,

Valence band maximum = 7.468149 eV
Conduction band minimum = 8.055196 eV
Warning: too many iterations in bisection
Ef = 0.000000
Mobility VB Fermi level 0.000000 eV
Valence band maximum = 7.468149 eV
Conduction band minimum = 8.055196 eV
Warning: too many iterations in bisection
Ef = 0.000000
Mobility CB Fermi level 0.000000 eV

Any suggestions to avoid this error are greatly appreciated!
Best,
Sai

[roxana]

Hi,

If you know where the Fermi level should be located you can provided in the input file through the flag fermi_energy.

Best,
Roxana