<div dir="ltr"><span style="font-family:arial,sans-serif;font-size:14px">Dear all,</span><div style="font-family:arial,sans-serif;font-size:14px"><br></div><div style="font-family:arial,sans-serif;font-size:14px">I have a question of matdyn.x .</div>
<div style="font-family:arial,sans-serif;font-size:14px">(This mail had sent once. Then no reply... )</div><div style="font-family:arial,sans-serif;font-size:14px"><br></div><div style="font-family:arial,sans-serif;font-size:14px">
I have calculated phonon dispersion of the materials of a one-dimensional system(Silicon nano wire). <br></div><div style="font-family:arial,sans-serif;font-size:14px">Then, the problem occurred. <br></div><div style="font-family:arial,sans-serif;font-size:14px">
First, I estimated the frequency of $B&#(B point using dynmat.x.(result is following)</div><div style="font-family:arial,sans-serif;font-size:14px">As for the result, frequencies also including rotation mode was set to 0. </div>
<div style="font-family:arial,sans-serif;font-size:14px"> <br></div><div style="font-family:arial,sans-serif;font-size:14px">Next, phonon dispersion of $B&#(B point to X point was calculated using matdyn.x (same structure). Much negative frequencies appeared.</div>
<div style="font-family:arial,sans-serif;font-size:14px"> </div><div style="font-family:arial,sans-serif;font-size:14px">Especially an amusing point is that negative frequency appeared of gamma point...</div><div style="font-family:arial,sans-serif;font-size:14px">
Is it strange!?!?!?!</div><div style="font-family:arial,sans-serif;font-size:14px">Negative frequency at gamma point did not appear in dynmat.x . </div><div style="font-family:arial,sans-serif;font-size:14px">But,negative frequency at gamma point appeared in matdyn.x . <br>
</div><div style="font-family:arial,sans-serif;font-size:14px"><br></div><div style="font-family:arial,sans-serif;font-size:14px">Please help me....</div><div style="font-family:arial,sans-serif;font-size:14px">MY input is so bad??????</div>
<div style="font-family:arial,sans-serif;font-size:14px">(see attach file)</div><div style="font-family:arial,sans-serif;font-size:14px"><br></div><div style="font-family:arial,sans-serif;font-size:14px">Best</div><div style="font-family:arial,sans-serif;font-size:14px">
<p style="background-color:transparent;margin:0px 15px 15px;padding:0px;border:0px;outline:0px;font-size:12px;vertical-align:baseline;color:rgb(85,85,85);font-family:Helvetica,Osaka,$B#M#S#P%4%7%C%/(B,Arial,sans-serif;line-height:18px">
Department of Applied Physics,<br>Graduate School of Engineering/Faculty of Engineering,<br>The University of Tokyo</p><p style="background-color:transparent;margin:0px 15px 15px;padding:0px;border:0px;outline:0px;font-size:12px;vertical-align:baseline;color:rgb(85,85,85);font-family:Helvetica,Osaka,$B#M#S#P%4%7%C%/(B,Arial,sans-serif;line-height:18px">
Building No. 6, Faculty of Engineerng, Hongo Campus<br>7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656<br>TEL: +81-3-5841-6800 FAX: +81-3-5841-6803</p><p style="background-color:transparent;margin:0px 15px 15px;padding:0px;border:0px;outline:0px;font-size:12px;vertical-align:baseline;color:rgb(85,85,85);font-family:Helvetica,Osaka,$B#M#S#P%4%7%C%/(B,Arial,sans-serif;line-height:18px">
AOSHIMA</p></div><div style="font-family:arial,sans-serif;font-size:14px"><br></div><div style="font-family:arial,sans-serif;font-size:14px">SCF inout</div><div style="font-family:arial,sans-serif;font-size:14px">---------------------<br>
</div><div style="font-family:arial,sans-serif;font-size:14px"><div> &control</div><div> calculation='scf'</div><div> restart_mode='restart',</div><div> prefix='100',</div><div> pseudo_dir = './',</div>
<div> outdir='./'</div><div> tprnfor = .true.</div><div> tstress = .true.</div><div> /</div><div> &system</div><div> ibrav=8,</div><div> celldm(1) = 9.633168021 ,</div><div> celldm(2) =3.480290431 ,</div>
<div> celldm(3) =3.480290431 ,</div><div>! celldm(3) = 3.472149983 ,</div><div> nat= 21,</div><div> ntyp= 2,</div><div> ecutwfc =80.0,</div><div> /</div><div> &electrons</div><div> diagonalization = 'cg'</div>
<div> conv_thr = 1.0d-12</div><div> mixing_beta = 0.2</div><div> electron_maxstep = 10000</div><div> /</div><div>ATOMIC_SPECIES</div><div> Si 28.086 Si.pz-vbc.UPF</div><div> H 1.00782503207 H.pz-vbc.UPF</div>
<div>ATOMIC_POSITIONS bohr</div><div>Si 2.382735185 4.187856452 4.187856452</div><div>Si 4.789323342 1.598574217 6.780983321</div><div>Si 7.195931863 4.187882682 9.374067631</div><div>Si 4.789323342 6.780983321 1.598574217</div>
<div>Si 7.195931863 9.374067631 4.187882682</div><div>Si -0.027228530 6.780971674 6.780971674</div><div>Si 2.382730459 9.374088640 9.374088640</div><div>Si 4.789318991 11.963373368 6.780966038</div>
<div>Si 4.789318991 6.780966038 11.963373368</div><div>H 0.571305371 2.642525984 2.642525984</div><div>H 3.058730990 -0.053715198 8.291361254</div><div>H 6.519883004 -0.053820395 5.270682330</div>
<div>H 9.007309318 2.642524144 10.919428308</div><div>H 3.058730990 8.291361254 -0.053715198</div><div>H 6.519883004 5.270682330 -0.053820395</div><div>H 9.007309318 10.919428308 2.642524144</div>
<div>H 0.571286047 10.919410757 10.919410757</div><div>H 6.519874014 13.615773142 8.291266823</div><div>H 3.058723946 13.615653717 5.270582379</div><div>H 6.519874014 8.291266823 13.615773142</div>
<div>H 3.058723946 5.270582379 13.615653717</div><div>K_POINTS AUTOMATIC</div><div>16 1 1 0 0 0</div><div><br></div><div><br></div><div><div>SCF output</div><div>---------------------</div></div><div><div> Total force = 0.000172 Total SCF correction = 0.000000</div>
<div><br></div><div> entering subroutine stress ...</div><div><br></div><div> total stress (Ry/bohr**3) (kbar) P= -0.20</div><div> 0.00000002 0.00000000 0.00000000 0.00 0.00 0.00</div>
<div> 0.00000000 -0.00000209 0.00000000 0.00 -0.31 0.00</div><div> 0.00000000 0.00000000 -0.00000209 0.00 0.00 -0.31</div><div><br></div><div style>PH.x input</div><div style>
-------------------</div><div style>phonons of sinw100<br></div><div style><div> &inputph</div><div> tr2_ph=1.0d-14,</div><div> prefix='100',</div><div> ldisp=.true.,</div><div> nq1=8, nq2=1, nq3=1</div><div>
amass(1)=28.08,</div><div> amass(2)=1.00782503207,</div><div> epsil = .true.,</div><div> outdir='./',</div><div> fildyn='100.dyn',</div><div> /</div><div><br></div><div style>dynmat input</div><div style>
------------------- </div><div style>&input fildyn='100.dyn1', asr='one-dim' , axis=1 /</div><div><br></div><div style>q2r input</div><div style>------------------</div><div style><div> &input</div>
<div> fildyn='100.dyn', zasr='one-dim', flfrc='100-811.fc' </div><div> /</div><div><br></div><div style>matdyn input</div><div style>-------------------</div><div style><div>&input</div><div>
asr='one-dim', amass(1)=28.08,amass(2)=1.0078</div><div> flfrc='100-411.fc' , flfrq='100.freq811', q_in_band_form=.true.</div><div>/</div><div>1</div><div>0.0 0.0 0.0 1</div><div><br></div>
<div><div>dynmat output</div><div>------------------- </div></div></div></div></div><div><div> omega( 1) = -0.000001 [THz] = -0.000036 [cm-1]</div><div> omega( 2) = 0.000000 [THz] = -0.000007 [cm-1]</div>
<div> omega( 3) = 0.000000 [THz] = -0.000004 [cm-1]</div><div> omega( 4) = 0.000000 [THz] = 0.000009 [cm-1]</div><div> omega( 5) = 2.459249 [THz] = 82.031704 [cm-1]</div><div>
omega( 6) = 2.716936 [THz] = 90.627231 [cm-1]</div><div> omega( 7) = 2.784694 [THz] = 92.887388 [cm-1]</div><div> omega( 8) = 3.192872 [THz] = 106.502734 [cm-1]</div><div> omega( 9) = 3.212233 [THz] = 107.148552 [cm-1]</div>
<div> omega(10) = 3.587636 [THz] = 119.670670 [cm-1]</div><div> omega(11) = 4.083911 [THz] = 136.224619 [cm-1]</div><div> omega(12) = 4.768755 [THz] = 159.068544 [cm-1]</div><div>
omega(13) = 4.975315 [THz] = 165.958655 [cm-1]</div><div> omega(14) = 5.001761 [THz] = 166.840795 [cm-1]</div><div> omega(15) = 6.892673 [THz] = 229.914826 [cm-1]</div><div> omega(16) = 9.192810 [THz] = 306.639122 [cm-1]</div>
<div> omega(17) = 10.513991 [THz] = 350.708984 [cm-1]</div><div> omega(18) = 10.524789 [THz] = 351.069187 [cm-1]</div><div> omega(19) = 10.617129 [THz] = 354.149289 [cm-1]</div><div>
omega(20) = 10.890637 [THz] = 363.272536 [cm-1]</div><div> omega(21) = 10.905409 [THz] = 363.765293 [cm-1]</div><div> omega(22) = 11.336427 [THz] = 378.142495 [cm-1]</div><div> omega(23) = 11.410636 [THz] = 380.617853 [cm-1]</div>
<div> omega(24) = 12.077304 [THz] = 402.855485 [cm-1]</div><div> omega(25) = 12.779812 [THz] = 426.288628 [cm-1]</div><div> omega(26) = 13.755479 [THz] = 458.833378 [cm-1]</div><div>
omega(27) = 13.984813 [THz] = 466.483148 [cm-1]</div><div> omega(28) = 14.013973 [THz] = 467.455822 [cm-1]</div><div> omega(29) = 14.472678 [THz] = 482.756590 [cm-1]</div><div> omega(30) = 14.500082 [THz] = 483.670669 [cm-1]</div>
<div> omega(31) = 14.502298 [THz] = 483.744595 [cm-1]</div><div> omega(32) = 15.827998 [THz] = 527.965169 [cm-1]</div><div> omega(33) = 16.083377 [THz] = 536.483716 [cm-1]</div><div>
omega(34) = 16.199758 [THz] = 540.365751 [cm-1]</div><div> omega(35) = 17.040062 [THz] = 568.395277 [cm-1]</div><div> omega(36) = 17.466808 [THz] = 582.630011 [cm-1]</div><div> omega(37) = 17.475967 [THz] = 582.935527 [cm-1]</div>
<div> omega(38) = 17.498416 [THz] = 583.684314 [cm-1]</div><div> omega(39) = 18.422937 [THz] = 614.523039 [cm-1]</div><div> omega(40) = 18.759100 [THz] = 625.736209 [cm-1]</div><div>
omega(41) = 18.770115 [THz] = 626.103635 [cm-1]</div><div> omega(42) = 18.827539 [THz] = 628.019117 [cm-1]</div><div> omega(43) = 19.699527 [THz] = 657.105484 [cm-1]</div><div> omega(44) = 20.041762 [THz] = 668.521221 [cm-1]</div>
<div> omega(45) = 20.150555 [THz] = 672.150180 [cm-1]</div><div> omega(46) = 20.221413 [THz] = 674.513735 [cm-1]</div><div> omega(47) = 20.393150 [THz] = 680.242262 [cm-1]</div><div>
omega(48) = 25.687718 [THz] = 856.850025 [cm-1]</div><div> omega(49) = 25.754448 [THz] = 859.075915 [cm-1]</div><div> omega(50) = 25.813670 [THz] = 861.051362 [cm-1]</div><div> omega(51) = 26.069795 [THz] = 869.594747 [cm-1]</div>
<div> omega(52) = 62.141810 [THz] = 2072.827649 [cm-1]</div><div> omega(53) = 62.166180 [THz] = 2073.640558 [cm-1]</div><div> omega(54) = 62.177946 [THz] = 2074.033021 [cm-1]</div><div>
omega(55) = 62.184502 [THz] = 2074.251710 [cm-1]</div><div> omega(56) = 62.706748 [THz] = 2091.671971 [cm-1]</div><div> omega(57) = 62.798498 [THz] = 2094.732409 [cm-1]</div><div> omega(58) = 62.839612 [THz] = 2096.103848 [cm-1]</div>
<div> omega(59) = 62.929713 [THz] = 2099.109272 [cm-1]</div><div> omega(60) = 63.241959 [THz] = 2109.524671 [cm-1]</div><div> omega(61) = 63.254255 [THz] = 2109.934849 [cm-1]</div><div>
omega(62) = 63.262039 [THz] = 2110.194482 [cm-1]</div><div> omega(63) = 63.281137 [THz] = 2110.831535 [cm-1]</div></div><div><br></div><div><br></div><div><div>matdyn output (100.freq811)</div><div>
-------------------</div></div></div><div><div> &plot nbnd= 63, nks= 1 /</div><div> 0.000000 0.000000 0.000000</div><div> -5.6995 -3.2089 -3.1656 -3.0713 83.7567 91.1907</div><div> 93.4933 106.4343 107.0925 118.3760 136.2249 159.4278</div>
<div> 165.9240 166.8070 229.9149 306.6390 350.6441 351.0409</div><div> 353.1550 363.4662 364.2095 377.9400 380.4193 403.0923</div><div> 426.2896 458.8340 466.4741 467.4453 482.6640 483.6529</div><div> 483.7281 527.9141 536.4779 540.3593 568.4037 582.6261</div>
<div> 582.9450 584.5624 614.5306 625.6785 626.0435 628.0315</div><div> 656.6387 668.5283 672.4869 674.8514 680.2558 856.8591</div><div> 859.0162 860.9915 869.6037 2072.8527 2073.6655 2074.0580</div><div> 2074.2786 2091.6973 2094.7864 2096.1588 2099.1353 2109.4521</div>
<div> 2109.9082 2110.1687 2110.8971</div></div><div><br></div><div><br></div></div></div>