Dear Wang<div><br></div><div>In my guess, the converging mostly depends on choosing pseudopotential, so may be it is the problem, that you are not getting converge Raman activity.</div><div>Otherhand, can you check your structure as well as, but i am not sure.</div>
<div><br></div><div>Best</div><div>Sanjeev</div><div><br><br><div class="gmail_quote">On Wed, May 29, 2013 at 5:22 AM, xirainbow <span dir="ltr"><<a href="mailto:nkxirainbow@gmail.com" target="_blank">nkxirainbow@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Dear all:<div> I calculated the "Raman activity" of diamond(Carbon) using QE-5.0. </div><div> The "Raman activity" changes too much with ecutwfc.</div>
<div> Could you give me some help?</div>
<div><br></div><div>Calculational results of "Raman activity variation with ecutwfc" ("14*14*14 kmesh).</div><div> ecutwfc(Ry) Freq(cm-1) Raman activity(A^4/amu)</div><div> 65 1330.23 68.9754</div>
<div> 100 1330.65 68.9674</div><div> 110 1330.50 3066.0811</div><div> 120 1330.48 15.1570</div><div> 130 1330.47 68.9545</div>
<div><br></div><div>The following is input of pw.x and ph.x:</div><div>INPUT of SCF:</div><div><div><div> &control</div><div> calculation='scf',</div><div> disk_io='low',</div><div> restart_mode='from_scratch',</div>
<div> prefix='diamond.$i'</div><div> pseudo_dir = '/home/lykong/hwang/espresso-5.0/pseudo',</div><div> outdir='/home/lykong/hwang/tmp'</div><div> /</div><div> &system</div><div> ibrav = 0, celldm(1) = 1.88972687777436, nat= 2, ntyp= 1,</div>
<div> ecutwfc = $i</div><div> /</div><div> &electrons</div><div> mixing_beta = 0.7</div><div> conv_thr = 1.0d-8</div><div> /</div><div>ATOMIC_SPECIES</div><div> C 12.01 C.pw-mt_fhi.UPF</div><div>ATOMIC_POSITIONS {crystal}</div>
<div>C 0.000000000 0.000000000 0.00000000</div><div>C 0.250000000 0.250000000 0.25000000</div></div></div><div><div>CELL_PARAMETERS</div><div> 1.758613117 1.758613117 0.000000000</div>
<div> 1.758613117 0.000000000 1.758613117</div><div> 0.000000000 1.758613117 1.758613117</div></div><div><br></div><div><br></div><div>INPUT of PHONON:</div><div><div>phonons of diamond at Gamma</div><div> &inputph</div>
<div> tr2_ph=1.0d-14,</div><div> alpha_mix=0.7</div><div> prefix='diamond.$i'</div><div> epsil=.true.,</div><div> lraman=.true.,</div><div> amass(1)=12.01,</div><div> outdir='/home/lykong/hwang/tmp'</div>
<div> fildyn='diamond.$i.dynG',</div><div> reduce_io=.TRUE.</div><div> /</div><div>0.0 0.0 0.0</div></div><span class="HOEnZb"><font color="#888888"><div><br></div><div> <br clear="all"><div><br></div>
-- <br>____________________________________<br>
Hui Wang<br>School of physics, Fudan University, Shanghai, China
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