Energy doesn't change under different external field

[shi_li]

Hi,

I am new to the vasp code and trying to reproduce a work in this paper: DOI: 10.1039/c7cp07270h.
I made the similar InSe slab and placed one H2 molecule on top of the In atom. After relaxation, I changed the external filed from 0.1 ~ 0.8 eV/Ang. But all the calculations returned the same energy. I tried to perform either single point calculation or relaxation under different field. But none of them changed the final energy. I am wondering if someone can give me some suggestions about where goes wrong.

Thanks,

Here is my POSCAR for this calculation:
temp.pdb
1.00000000000000
11.8306878498999701 -0.0011226719275882 -0.0007440449527782
-5.9145269139286922 10.2464359367728317 0.0003862429413275
0.0082691886378547 0.0117577228058858 29.3918356411976269
In Se H
18 18 2
Direct
0.0556675731264525 0.1100717404451059 0.5453690546550614
0.0557113305718582 0.4452573682169025 0.5453920469662821
0.0539505397497285 0.7767866526113572 0.5452658247384653
0.3890276701917612 0.1119863097447793 0.5452989356552332
0.3872876739689571 0.4435473185662096 0.5451278922870109
0.3890464262953813 0.7767739875425022 0.5453083515110276
0.7204651459219593 0.1101129832159662 0.5454292800226985
0.7223145101755739 0.4434242867651759 0.5451055654399140
0.7223480135209004 0.7785472672261686 0.5451088121262990
0.0558009404897700 0.1102090474668294 0.4510178300778784
0.0558515191318553 0.4453848214763814 0.4510418066454853
0.0540498847891065 0.7769292949795557 0.4509130442426738
0.3891365885923466 0.1121250881016405 0.4509277318842740
0.3878788211545929 0.4438976443664460 0.4506615283733946
0.3891400008449774 0.7768464554459689 0.4509362573376033
0.7205513386659000 0.1101971353988070 0.4510736349734357
0.7221203440092921 0.4438373739105516 0.4506437232154506
0.7221739556168720 0.7781204711674768 0.4506520879865401
0.2773451346609592 0.2220274876312638 0.5917822677093124
0.2774018031369570 0.5550260745282771 0.5918098855030726
0.2772914539310697 0.8884571963299972 0.5908283435094642
0.6105467818808297 0.2219970730059016 0.5918296407142751
0.6105327565819414 0.5550710369308518 0.5905266164440153
0.6105722244881290 0.8882021173583706 0.5918020465673181
0.9438398348451087 0.2217137736338488 0.5909159482492793
0.9436173093269202 0.5550063072739946 0.5917603470533015
0.9436319014709144 0.8881969645104925 0.5917553560440695
0.2774273533239230 0.2219731990960320 0.4043916939052830
0.2774448012682931 0.5553681721749648 0.4043846414662308
0.2775765178800014 0.8887348694652852 0.4054623099746616
0.6108384092301686 0.2219106020115846 0.4043898292327466
0.6108691373484403 0.5553694249655989 0.4047891301780300
0.6108768242622193 0.8888226360457422 0.4044088726236209
0.9441111843134117 0.2220267025880411 0.4055721756137224
0.9442939105309145 0.5553775174223980 0.4044128344126835
0.9443017943590573 0.8888078716294688 0.4043811996470433
0.6079541257496790 0.5559198197100303 0.7186279866599563
0.6077755516297535 0.5550079284686218 0.6930490930657017


Here is the INCAR I used base on the description in the paper, I varied the EFILED value from 0.1 to 0.8:
ISTART = 0
ISPIN = 2
ENCUT = 325
NELM = 100
NELMIN = 2
LREAL = A
IVDW = 10
ISYM = 0

EFIELD = NUMBER
LDIPOL = .TRUE.
IDIPOL = 3

GGA = PE

NSW = 0
ISMEAR = 0
SIGMA = 0.2
IBRION = 2
ISIF = 2
EDIFFG = -2E-02
PREC = Accurate
EDIFF = 1E-6

[pedro_melo]

Dear shi_li,

Was this a Gamma-only calculation? If not, how many k-points did you use?

Kind regards,
Pedro Melo

[shi_li]

Hi Pedro,

Thanks for your reply. I am using a 8*8*1 Monkhorst–Pack k-points.

Shi

Dear shi_li,

Was this a Gamma-only calculation? If not, how many k-points did you use?

Kind regards,
Pedro Melo

[pedro_melo]

Dear Shi,

My apologies, I forgot to ask: which version of VASP are you using?

Kind regards,
Pedro Melo

[shi_li]

Hi Pedro,

I am using the version 5.4.4.

Shi

Dear Shi,

My apologies, I forgot to ask: which version of VASP are you using?

Kind regards,
Pedro Melo