Interpretation of Results

[dwaipayanroni]

Hi,
My system has 76 atoms and no of valence electron, NELECT = 216 and the no of band is 148 (KPOINTS = 400). I just want to calculate the effective mass at conduction band maxima (CBM) (gamma point in this case), for that I have modified the EIGENVAL file. I changed the no of electrons = 2, no of bands = 1 and taken just 5 KPOINTS adjacent to the gamma point and the eigenvalue corresponding to the CB at each KPOINT is only there. But the problem is I cannot interprete the result. the output is like this:

Hello world! Imports successful...
unknown: 2 npoints: 5 nbands: 1
[0.847645, 0.847612, 0.847513, 0.847347, 0.847115]

Band...[0.847645, 0.847612, 0.847513, 0.847347, 0.847115]
Extrema look like: {k_x}=[-16.645, -14.5137, -12.3641, -10.1891, -7.97972, -5.71736, -3.33451, 1.33935, 2.40693, 3.24722, 3.92593, 4.69036, 9.34885, 11.6625, 13.8519, 15.9947, 18.1177, 20.2347]
Energy at Extrema: f({k_x})=[0.0722668, 0.209253, 0.0737504, 0.213902, 0.0595428, 0.246182, -0.0197813, 0.849561, 0.847084, 0.847599, 0.847337, 0.848062, -0.0489222, 0.273334, 0.0364161, 0.231943, 0.0614327, 0.21549]
f''({k_x}) at Extrema: =[0.15244, -0.146085, 0.144493, -0.149583, 0.165281, -0.1999, 0.275745, -0.0228425, 0.00519049, -0.00277986, 0.0034623, -0.0123938, 0.337427, -0.266705, 0.225104, -0.197297, 0.177409, -0.162828]
Effective masses: [0.40709, -0.4248, 0.429479, -0.414866, 0.375464, -0.310439, 0.225052, -2.71673, 11.9559, -22.3237, 17.9236, -5.00708, 0.183912, -0.23268, 0.275681, -0.314535, 0.349796, -0.38112]

I have also attached the EIGENVAL and plot.png file. I want to know what is the value of the effective mass at the CBM i.e. at the gamma point on the CB.

EIGENVAL.zip

Thanks,
Dwaipayan Chakraborty