Actually I have used esm_bc to add vacuum in the structure.How can I add vacuum in this monolayer WSE2 structure using quantum espresso.Which code should be used.<br><br>On Wednesday, March 1, 2017, Giovanni Cantele <<a href="mailto:giovanni.cantele@spin.cnr.it">giovanni.cantele@spin.cnr.it</a>> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">It is not clear how and to what extend your band structure differs from shat you expect.<br>
However, one issue I can see is that if you want to study MONOLAYER WSe2, you should be aware of the fact that the vacuum space, separating the periodic replicas<br>
along your z direction should be large enough to prevent them from interacting (otherwise, you are considering a periodic crystal also along<br>
that direction). Currently, as far as I can see such vacuum is < 5A, definitely too small to simulate a monolayer. Additionally, you also include vdw_corr, usually introduced<br>
to better describe inter-layer interaction, whereas you are claiming that you want to study a system composed by a single layer.<br>
Also, I think that you don’t need to use the variable esm_bc just to calculate the properties of a monolayer.<br>
<br>
Giovanni<br>
<br>
<br>
<br>
<br>
> On 1 Mar 2017, at 14:01, Anindya Bose <<a href="javascript:;" onclick="_e(event, 'cvml', 'anindya@iiita.ac.in')">anindya@iiita.ac.in</a>> wrote:<br>
><br>
> Dear Sir,<br>
><br>
> &CONTROL<br>
> calculation='nscf',<br>
> outdir='monolayer WSe2',<br>
> prefix='calc',<br>
> pseudo_dir='/home/anindya/<wbr>Desktop/pseudopotentials',<br>
> verbosity='low',<br>
> disk_io='high',<br>
> wf_collect=.true.,<br>
> etot_conv_thr=1d-02,<br>
> forc_conv_thr=1d-02,<br>
> /<br>
><br>
> &SYSTEM<br>
> noncolin=.true.,<br>
> lspinorb=.true.,<br>
> ibrav=0,<br>
> celldm(1)=6.2020811408d0, celldm(3)=4.3566118221d0,<br>
> nat=3,<br>
> ntyp=2,<br>
> ecutwfc=40.0d0,<br>
> nbnd=200,<br>
> vdw_corr='Grimme-D2',<br>
> starting_magnetization=0.05,<br>
> force_symmorphic=.true.,<br>
> input_dft='PBE',<br>
> esm_bc='bc1',<br>
> no_t_rev=.false.,<br>
> /<br>
><br>
> &ELECTRONS<br>
> diagonalization='david',<br>
> conv_thr=1d-08,<br>
> mixing_mode='plain',<br>
> mixing_beta=0.700d0,<br>
> /<br>
><br>
> &ions<br>
> ion_dynamics ='bfgs',<br>
> /<br>
><br>
> &cell<br>
> cell_dynamics ='bfgs',<br>
> cell_factor=15,<br>
> /<br>
><br>
> ATOMIC_SPECIES<br>
> Se 78.960000d0 Se_ONCV_PBE-1.0_nr.oncvpsp.upf<br>
> W 183.840000d0 W_ONCV_PBE-1.1_nr.oncvpsp.upf<br>
><br>
> CELL_PARAMETERS (alat= 6.20208114)<br>
> 1.008112278 0.000000000 0.000000000<br>
> -0.504056139 0.873050842 0.000000000<br>
> 0.000000000 0.000000000 2.445357065<br>
><br>
> ATOMIC_POSITIONS {alat}<br>
> W 0.504056139 0.291016947 1.222674975<br>
> Se 0.504056139 -0.291016947 0.699051439<br>
> Se 0.504056139 -0.291016947 1.746298512<br>
><br>
><br>
> K_POINTS {crystal_b}<br>
> 4<br>
> # Gamma-K-M-Gamma<br>
> 0 0 0 20 !G<br>
> 0.33 0.33 0 20 !K<br>
> 0.5 0 0 20 !M<br>
> 0 0 0 20 !G<br>
><br>
> I am not getting the WSe2 monolayer band structure, can you please help me in this regard.<br>
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<br>
--<br>
<br>
Giovanni Cantele, PhD<br>
CNR-SPIN<br>
c/o Dipartimento di Fisica<br>
Universita' di Napoli "Federico II"<br>
Complesso Universitario M. S. Angelo - Ed. 6<br>
Via Cintia, I-80126, Napoli, Italy<br>
e-mail: <a href="javascript:;" onclick="_e(event, 'cvml', 'giovanni.cantele@spin.cnr.it')">giovanni.cantele@spin.cnr.it</a><br>
Phone: +39 081 676910<br>
Skype contact: giocan74<br>
<br>
ResearcherID: <a href="http://www.researcherid.com/rid/A-1951-2009" target="_blank">http://www.researcherid.com/<wbr>rid/A-1951-2009</a><br>
Web page: <a href="http://people.na.infn.it/~cantele" target="_blank">http://people.na.infn.it/~<wbr>cantele</a><br>
<br>
<br>
<br>
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