Yes, I suppose so, but it is not easy to say exactly how it has to be
done in this case (H or OH saturation? surface reconstruction?). If
you are lucky, you may find something in literature...
Best
Giuseppe
LEUNG Clarence <[email protected]> ha scritto:
Dear Giuseppe,
Thanks for your suggest.
My structure is (3 1 0) surface of Co3(PO4)2 with 15 angstrom
vacuum. You mean that the unsaturated bond should be passivated by H
or something？
LIANG Xiongyi
________________________________
发件人: users <[email protected]> 代表 Giuseppe
Mattioli <[email protected]>
发送时间: 2018年12月19日 19:30
收件人: [email protected]
主题: Re: [QE-users] DFT+U can not converge
Dear Liang Xiongyi
In my opinion, your initial structure is possibly wrong or missing
necessary saturation (i.e. twofold-coordinated P atoms on the surface
and P=O free terminations, which are likely unstable in gas phase).
However, and generally speaking, if your calculation is going
somewhere not so far from convergence, you can overcome a difficult
initial step by using this very useful switch:
scf_must_converge=.false.
Coupled with a suitable electron_maxstep variable, it will calculate
forces and move atoms when scf ends. If the structure is meaningful
and not wrong (and this may not be the case) in a few steps you should
recover an acceptably smooth convergence.
HTH
Giuseppe
LEUNG Clarence <[email protected]> ha scritto:
Dear QEusers,
When I use QE6.3 to perform DFT+U to relax a slab, it is very
difficult to converge and even can not converge (more than 300 scf
steps). Thanks for your suggestion in advances.
The input file is:
&CONTROL
calculation='relax',
nstep = 200 ,
wf_collect = .true. ,
etot_conv_thr = 3.5D-6 ,
forc_conv_thr = 4.0D-4,
/
&SYSTEM
ibrav=0,
celldm(1)=9.6431795847d0,
nat=109,
ntyp=3,
ecutwfc=60,
ecutrho=480,
input_dft='PBE',
occupations='smearing',
smearing = 'gaussian' ,
degauss = 0.01 ,
nspin = 2 ,
starting_magnetization(1) = 0.5 ,
lda_plus_u = .true. ,
Hubbard_U(1) = 3.32 ,
vdw_corr = dft-d3 ,
/
&ELECTRONS
conv_thr=1d-05,
mixing_beta=0.3d0,
mixing_mode ='local-TF',
electron_maxstep = 600 ,
/
&IONS
/
&CELL
/
ATOMIC_SPECIES
Co 58.933200d0 Co.pbe-spn-rrkjus_psl.0.3.1.UPF
O 15.999400d0 O.pbe-n-rrkjus_psl.1.0.0.UPF
P 30.973800d0 P.pbe-n-rrkjus_psl.1.0.0.UPF
ATOMIC_POSITIONS {crystal}
O 0.175510868 0.823201091 0.004041902 0 0 0
Co 0.752963028 0.655948399 0.004313566 0 0 0
O 0.301125723 0.416151961 0.004879997 0 0 0
Co 0.846799898 0.775755648 0.005275182 0 0 0
Co 0.346800351 0.275755641 0.005275204 0 0 0
O 0.392474471 0.135359341 0.005670234 0 0 0
Co 0.940637166 0.895562903 0.006236666 0 0 0
O 0.518089326 0.728310212 0.006508330 0 0 0
O 0.902313840 0.059368885 0.017959393 0 0 0
O 0.807187857 0.964594997 0.020457557 0 0 0
O 0.036878250 0.705581722 0.023890599 0 0 0
P 0.893919682 0.538810250 0.026242849 0 0 0
Co 0.451343782 0.481124665 0.033750041 0 0 0
O 0.028914218 0.314809876 0.034323347 0 0 0
P 0.323165643 0.700374526 0.044655886 0 0 0
O 0.412931350 0.644218586 0.045243797 0 0 0
O 0.180081232 0.532598515 0.046685149 0 0 0
O 0.551818853 0.324973894 0.062282695 0 0 0
O 0.318968869 0.213353805 0.063724007 0 0 0
P 0.408734429 0.157197863 0.064311920 0 0 0
O 0.702985853 0.542762514 0.074644459 0 0 0
Co 0.280556437 0.376447725 0.075217763 0 0 0
P 0.837980537 0.318762141 0.082724954 0 0 0
O 0.695021832 0.151990660 0.085077236 0 0 0
O 0.924712372 0.892977386 0.088510276 0 0 0
O 0.829586379 0.798203506 0.091008410 0 0 0
O 0.213810893 0.129262179 0.102459474 0 0 0
Co 0.791263053 0.962009487 0.102731138 0 0 0
O 0.339425748 0.722213050 0.103297569 0 0 0
Co 0.885099923 0.081816736 0.103692754 0 0 0
Co 0.385100377 0.581816730 0.103692776 0 0 0
O 0.430774496 0.441420429 0.104087807 0 0 0
Co 0.978937191 0.201623991 0.104654238 0 0 0
O 0.556389351 0.034371300 0.104925902 0 0 0
O 0.940613865 0.365429972 0.116376965 0 0 0
O 0.845487883 0.270656085 0.118875129 0 0 0
O 0.075178275 0.011642810 0.122308171 0 0 0
P 0.932219708 0.844871338 0.124660421 0 0 0
Co 0.489643808 0.787185753 0.132167613 0 0 0
O 0.067214244 0.620870964 0.132740919 0 0 0
P 0.361354279 0.006083789 0.142115621
O 0.446802131 0.950135511 0.145110715
O 0.214381915 0.837791409 0.146887224
O 0.593110221 0.629859448 0.161855388
O 0.355569602 0.519337757 0.162613913
P 0.444333889 0.463046511 0.162481449
O 0.733915313 0.849462282 0.171314557
Co 0.331397450 0.684149370 0.174777754
P 0.880835007 0.624048906 0.181575275
O 0.729016571 0.457586972 0.184340848
O 0.943694570 0.199413194 0.185888622
O 0.842699539 0.103890146 0.188690045
O 0.246376254 0.435621465 0.201025875
Co 0.819907469 0.267437250 0.200281311
O 0.371654672 0.028624679 0.201597106
Co 0.919293748 0.386217687 0.198228118
Co 0.408991643 0.881622266 0.208931455
O 0.502982285 0.747275057 0.201700410
Co 0.015942502 0.506736170 0.203798000
O 0.581988259 0.338815157 0.205761317
O 0.989082264 0.670263393 0.214923633
O 0.891588821 0.575388161 0.217463006
O 0.102116329 0.316952504 0.225311380
P 0.946018990 0.150667428 0.220957196
Co 0.509889754 0.092572883 0.231027714
O 0.087929910 0.910622245 0.254736182
P 0.390071467 0.310008795 0.243522265
O 0.475452219 0.253683339 0.241349488
O 0.235229551 0.143749020 0.238654386
O 0.612387032 0.940393783 0.254302766
O 0.441611912 0.824444770 0.264038723
P 0.540200975 0.770461487 0.260363655
O 0.761099937 0.156388759 0.269996408
Co 0.350068981 0.991380761 0.270128489
P 0.873321153 0.936340371 0.286294166
O 0.833246668 0.765227606 0.276230271
O -0.000361722 0.500532992 0.288698932
O 0.881119075 0.405321157 0.282221320
O 0.360000301 0.737045056 0.298351129
Co 0.882972312 0.575549749 0.299644501
O 0.422605865 0.327653597 0.304586136
Co 0.978817281 0.686215697 0.299070830
Co 0.413208161 0.191270814 0.293687127
O 0.508789991 0.058470538 0.306778792
Co 0.104885226 0.777001345 0.337018699
O 0.655258778 0.642479617 0.299146914
O -0.013826595 0.991404406 0.298780328
O 0.795664337 0.914010571 0.342626007
O 0.182057906 0.620327437 0.315087245
P -0.025531312 0.449691921 0.318993246
Co 0.536676633 0.394337417 0.322803232
O 0.111523355 0.238614584 0.330445421
P 0.458259125 0.623697091 0.344422574
O 0.563543106 0.565239764 0.345713118
O 0.245933114 0.438564927 0.345886633
O 0.755827316 0.261536514 0.398125722
O 0.347085887 0.142061029 0.350995120
P 0.418798485 0.087516712 0.363471914
O 0.760091719 0.450332386 0.364446953
Co 0.425302156 0.268828519 0.364933404
P 1.000978059 0.228830728 0.389926937
O 0.665322447 0.083338404 0.398947262
O 0.175348426 0.819170270 0.393432843
O 0.972375724 0.715594688 0.364967608
O 0.192491280 0.055768375 0.386972733
Co 0.947698792 0.864533921 0.380242742
O 0.461116896 0.646777652 0.398656956
Co -0.128695091 0.044030025 0.349922760
Co 0.459662371 0.500794114 0.364054027
K_POINTS {automatic}
3 3 1 0 0 0
CELL_PARAMETERS {alat}
1.000000000000d0 0.000000000000d0 0.000000000000d0
-0.125138500246d0 5.222389311845d0 0.000000000000d0
0.000000000000d0 0.000000000000d0 4.847983163860d0
LIANG Xiongyi
CIty University of Hong Kong
GIUSEPPE MATTIOLI
CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
Via Salaria Km 29,300 - C.P. 10
I-00015 - Monterotondo Scalo (RM)
Mob (*preferred*) +39 373 7305625
Tel + 39 06 90672342 - Fax +39 06 90672316
E-mail: <[email protected]>
_______________________________________________
users mailing list
[email protected]
https://lists.quantum-espresso.org/mailman/listinfo/users
GIUSEPPE MATTIOLI
CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
Via Salaria Km 29,300 - C.P. 10
I-00015 - Monterotondo Scalo (RM)
Mob (*preferred*) +39 373 7305625
Tel + 39 06 90672342 - Fax +39 06 90672316
E-mail: <[email protected]>
_______________________________________________
users mailing list
[email protected]
https://lists.quantum-espresso.org/mailman/listinfo/users
