[Pw_forum] no band gap appear in the bands eigenvalues in relaxtion though a 3 ev band gaps should be found

[Yong Xue]

Dear all
I am doing relaxation for a system of C, O, and H2 which should have a 3eV
band gap. however, in my relaxation calculation, from the eigenvalues it
shows no band gap. So, I cannot trust the further nmr reulst. after this
step. I also paste my input for relax down, can anybody tell me what is the
problem?
as seen:

k = 0.0000 0.0000 0.0000 ( 74723 PWs) bands (ev):

-23.3453 -23.2509 -23.2259 -23.1667 -23.1380 -23.1122 -23.0976 -23.0482

-23.0458 -23.0391 -23.0106 -22.9744 -22.9539 -22.8721 -22.8682 -22.8455

-22.3021 -22.2631 -22.2033 -22.1970 -22.1484 -22.1315 -22.1282 -22.0954

-22.0871 -22.0694 -22.0552 -22.0311 -22.0123 -21.9204 -21.9035 -21.8837

-8.4344 -8.3878 -8.3473 -8.3270 -8.3022 -8.2845 -8.2588 -8.2276

-8.1713 -8.1558 -8.1257 -8.1136 -8.0572 -8.0456 -8.0142 -7.8924

-7.6997 -7.6605 -7.6189 -7.5822 -7.5252 -7.4844 -7.4585 -7.4155

-7.3812 -7.3456 -7.3208 -7.2927 -7.2727 -7.2064 -7.1959 -7.1331

-7.0934 -7.0671 -7.0557 -7.0208 -7.0045 -6.9641 -6.9386 -6.8821

-6.8590 -6.8208 -6.7835 -6.7601 -6.7139 -6.6954 -6.6775 -6.6429

-6.6383 -6.6099 -6.5706 -6.5443 -6.5219 -6.4977 -6.4694 -6.4132

-6.3866 -6.3671 -6.3464 -6.3133 -6.2895 -6.2532 -6.2271 -6.1256

-5.3074 -5.0504 -4.9293 -4.8727 -4.7052 -4.6028 -4.5628 -4.4287

-4.3984 -4.2942 -4.2714 -4.1638 -4.0900 -4.0423 -3.9205 -3.8424

-3.5850 -3.5379 -3.5217 -3.4738 -3.4482 -3.4294 -3.4036 -3.3727

-3.3479 -3.3346 -3.3131 -3.2836 -3.2617 -3.2478 -3.2094 -3.2018

-3.1871 -3.1527 -3.1299 -3.1174 -3.0990 -3.0931 -3.0428 -3.0157

-2.9912 -2.9617 -2.9398 -2.9352 -2.8936 -2.8767 -2.8479 -2.8174


&CONTROL

calculation = 'relax'

restart_mode = 'from_scratch'

prefix = 'CO2-H2-recover_product_nmr'

tstress = .true.

tprnfor = .true.

nstep=500,

dt=50,

pseudo_dir = './'

outdir = './scratch/'

/

&SYSTEM

ibrav = 0

celldm(1) = 1.889726164

nat = 80

ntyp = 3

ecutwfc = 80.000

ecutrho = 800.0

nosym = .true.

/

&electrons

mixing_beta = 0.7

conv_thr = 1.0d-8

/

&IONS

ion_dynamics='bfgs'

upscale=20,

/

CELL_PARAMETERS alat

9.9705270608830947 -0.0263506434352082 -0.3371859913906344

-0.0182095492082954 8.1336917725945508 -0.3120449570661378

-0.4215858584102301 -0.4581954945537299 11.3361129017285922

ATOMIC_SPECIES

H 1.00000 H.pbe-tm-gipaw.UPF

C 12.00000 C.pbe-tm-gipaw.UPF

O 16.00000 O.pbe-tm-gipaw.UPF

ATOMIC_POSITIONS crystal

thanks in advance

Xue
-- 
Ms. Xue  Yong(雍雪)
Department of Physics and Engineering Physics
University of Saskatchewan
116 Science Place
Saskatoon, SK S7N 5E2
Canada
Tel: +1 306 261 2369
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