How can I get the value of band gap.
Posted: Sun Apr 01, 2012 6:09 pm
I performed density of states calculations with pbe functionals for the Si unit cell.
I got the appropriate DOSCAR file from the calculation like this..
The fermi energy is "5.91004604 eV"
From the DOSCAR file, how can I measure the energy band gap under the value.
The density state is not zero at the fermi energy but the value is quite low. (E-02, E-04, E-08 ...)
I am very confused to analyze the data. Is there any criterion to measure the band gap?
Thank you very much.
DOSCAR file
...
...
...
4.695 0.4806E+01 0.3069E+02
4.771 0.3900E+01 0.3098E+02
4.846 0.2762E+01 0.3119E+02
4.922 0.2206E+01 0.3136E+02
4.998 0.1603E+01 0.3148E+02
5.074 0.1286E+01 0.3158E+02
5.150 0.6942E+00 0.3163E+02
5.226 0.7609E+00 0.3169E+02
5.302 0.1212E+01 0.3178E+02
5.378 0.8948E+00 0.3185E+02
5.454 0.7330E+00 0.3191E+02
5.529 0.7940E+00 0.3197E+02
5.605 0.3776E+00 0.3199E+02
5.681 0.6343E-01 0.3200E+02
5.757 0.3654E-02 0.3200E+02
5.833 0.7084E-04 0.3200E+02
5.909 0.4549E-06 0.3200E+02
5.985 0.1457E-08 0.3200E+02
6.061 0.2832E-06 0.3200E+02
6.137 0.5239E-04 0.3200E+02
6.212 0.3208E-02 0.3200E+02
6.288 0.6631E-01 0.3201E+02
6.364 0.4810E+00 0.3204E+02
6.440 0.1350E+01 0.3214E+02
6.516 0.1830E+01 0.3228E+02
6.592 0.1453E+01 0.3239E+02
6.668 0.5936E+00 0.3244E+02
6.744 0.3243E+00 0.3246E+02
6.820 0.1235E+01 0.3256E+02
6.895 0.2551E+01 0.3275E+02
6.971 0.2584E+01 0.3295E+02
7.047 0.2165E+01 0.3311E+02
7.123 0.3131E+01 0.3335E+02
7.199 0.4154E+01 0.3366E+02
...
...
...
...
<span class='smallblacktext'>[ Edited ]</span>
I got the appropriate DOSCAR file from the calculation like this..
The fermi energy is "5.91004604 eV"
From the DOSCAR file, how can I measure the energy band gap under the value.
The density state is not zero at the fermi energy but the value is quite low. (E-02, E-04, E-08 ...)
I am very confused to analyze the data. Is there any criterion to measure the band gap?
Thank you very much.
DOSCAR file
...
...
...
4.695 0.4806E+01 0.3069E+02
4.771 0.3900E+01 0.3098E+02
4.846 0.2762E+01 0.3119E+02
4.922 0.2206E+01 0.3136E+02
4.998 0.1603E+01 0.3148E+02
5.074 0.1286E+01 0.3158E+02
5.150 0.6942E+00 0.3163E+02
5.226 0.7609E+00 0.3169E+02
5.302 0.1212E+01 0.3178E+02
5.378 0.8948E+00 0.3185E+02
5.454 0.7330E+00 0.3191E+02
5.529 0.7940E+00 0.3197E+02
5.605 0.3776E+00 0.3199E+02
5.681 0.6343E-01 0.3200E+02
5.757 0.3654E-02 0.3200E+02
5.833 0.7084E-04 0.3200E+02
5.909 0.4549E-06 0.3200E+02
5.985 0.1457E-08 0.3200E+02
6.061 0.2832E-06 0.3200E+02
6.137 0.5239E-04 0.3200E+02
6.212 0.3208E-02 0.3200E+02
6.288 0.6631E-01 0.3201E+02
6.364 0.4810E+00 0.3204E+02
6.440 0.1350E+01 0.3214E+02
6.516 0.1830E+01 0.3228E+02
6.592 0.1453E+01 0.3239E+02
6.668 0.5936E+00 0.3244E+02
6.744 0.3243E+00 0.3246E+02
6.820 0.1235E+01 0.3256E+02
6.895 0.2551E+01 0.3275E+02
6.971 0.2584E+01 0.3295E+02
7.047 0.2165E+01 0.3311E+02
7.123 0.3131E+01 0.3335E+02
7.199 0.4154E+01 0.3366E+02
...
...
...
...
<span class='smallblacktext'>[ Edited ]</span>