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<p>I forgo to say, but should be evident, that alpha=1,2 and 3
correspond to x, y and z respectively, and the same for beta.<br>
</p>
<p><br>
</p>
<div class="moz-cite-prefix">On 13/06/2024 20:43, Lorenzo Paulatto
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:6c2def4c-a54e-4352-9082-d3096e2f0084@cnrs.fr"> 4
4 4
<br>
1 1 1 1
<br>
1 1 1 2.72193485518E-01
<br>
2 1 1 -3.66360766085E-03
<br>
3 1 1 -5.82906438331E-05
<br>
<br>
nq1 nq2 nq3
<br>
alpha beta I J
<br>
i1 j1 k1 F1
<br>
i2 j2 k2 F2
<br>
...
<br>
<br>
F1 is the force constant F(R1+tau_I^alpha, tau_J^beta).
<br>
<br>
Where R1 = (i1-1)*a1 + (j1-1)*a2 + (k1-1)*a3, with a1, a2, a3 the
lattice vectors; tau_I is the basis of atom I in the unit cell.
<br>
Translational invariance is used to have the second R (associated
with tau_J) always vanishing.
<br>
<br>
alpha and beta are Cartesian directions (x, y, z). The unit of
measure is Ry/bohr^2
<br>
<br>
<br>
alpha,beta = x,y,z
<br>
I,J = 1,... nat
<br>
<br>
With Nq = nq1*nq2*nq3 then
<br>
i_1... i_Nq = 1,... nq1
<br>
j_1... j_Nq = 1,... nq2
<br>
k_1... k_Nq = 1,... nq3
<br>
<br>
It is complicated, but not difficult.
<br>
<br>
hth
<br>
<br>
On 13/06/2024 19:33, Md. Jahid Hasan Sagor wrote:
<br>
<blockquote type="cite">Hi,
<br>
<br>
Below here- I am sharing inter atomic force constant file
content (*.ifc)
<br>
generated by quantum espresso. Could someone explain me what
does these number means? I have used nq1*nq2*nq3=4 * 4 * 4 in
ph.in <a class="moz-txt-link-rfc2396E" href="http://ph.in"><http://ph.in></a> (q grids)
<br>
<br>
<br>
4 4 4
<br>
1 1 1 1
<br>
1 1 1 2.72193485518E-01
<br>
2 1 1 -3.66360766085E-03
<br>
3 1 1 -5.82906438331E-05
<br>
4 1 1 -3.66360766085E-03
<br>
1 2 1 9.15317439765E-03
<br>
2 2 1 -3.16229448375E-04
<br>
3 2 1 1.03820610061E-04
<br>
4 2 1 -3.66360766085E-03
<br>
1 3 1 3.90322317374E-03
<br>
2 3 1 -3.16229448375E-04
<br>
3 3 1 -5.82906438331E-05
<br>
4 3 1 -3.16229448375E-04
<br>
1 4 1 9.15317439765E-03
<br>
2 4 1 -3.66360766085E-03
<br>
3 4 1 1.03820610061E-04
<br>
4 4 1 -3.16229448375E-04
<br>
1 1 2 -3.66360766085E-03
<br>
2 1 2 1.03820610061E-04
<br>
3 1 2 -3.16229448375E-04
<br>
4 1 2 9.15317439765E-03
<br>
1 2 2 -3.16229448375E-04
<br>
2 2 2 -2.73229894024E-04
<br>
3 2 2 -3.16229448375E-04
<br>
4 2 2 -4.98908734409E-04
<br>
1 3 2 -3.16229448375E-04
<br>
2 3 2 1.03820610061E-04
<br>
3 3 2 -2.17343457160E-04
<br>
4 3 2 -2.78788521756E-04
<br>
1 4 2 -3.66360766085E-03
<br>
2 4 2 -2.36600242622E-04
<br>
3 4 2 -2.17343457160E-04
<br>
4 4 2 -4.98908734409E-04
<br>
1 1 3 -5.82906438331E-05
<br>
2 1 3 -3.16229448375E-04
<br>
3 1 3 3.90322317374E-03
<br>
4 1 3 -3.16229448375E-04
<br>
1 2 3 1.03820610061E-04
<br>
2 2 3 -3.16229448375E-04
<br>
3 2 3 -2.78788521756E-04
<br>
4 2 3 -2.17343457160E-04
<br>
1 3 3 -5.82906438331E-05
<br>
2 3 3 -2.17343457160E-04
<br>
3 3 3 -2.42602344837E-04
<br>
4 3 3 -2.17343457160E-04
<br>
1 4 3 1.03820610061E-04
<br>
2 4 3 -2.17343457160E-04
<br>
3 4 3 -2.78788521756E-04
<br>
4 4 3 -3.16229448375E-04
<br>
1 1 4 -3.66360766085E-03
<br>
2 1 4 9.15317439765E-03
<br>
3 1 4 -3.16229448375E-04
<br>
4 1 4 1.03820610061E-04
<br>
1 2 4 -3.66360766085E-03
<br>
2 2 4 -4.98908734409E-04
<br>
3 2 4 -2.17343457160E-04
<br>
4 2 4 -2.36600242622E-04
<br>
1 3 4 -3.16229448375E-04
<br>
2 3 4 -2.78788521756E-04
<br>
3 3 4 -2.17343457160E-04
<br>
4 3 4 1.03820610061E-04
<br>
1 4 4 -3.16229448375E-04
<br>
2 4 4 -4.98908734409E-04
<br>
3 4 4 -3.16229448375E-04
<br>
4 4 4 -2.73229894024E-04
<br>
1 1 1 2
<br>
1 1 1 -6.65118280325E-02
<br>
2 1 1 -6.65118280325E-02
<br>
3 1 1 -5.60776424931E-04
<br>
4 1 1 -5.60776424931E-04
<br>
1 2 1 -6.65118280325E-02
<br>
2 2 1 8.23931384971E-04
<br>
3 2 1 -1.01851073716E-04
<br>
4 2 1 1.23351993366E-04
<br>
1 3 1 -4.82771934254E-03
<br>
2 3 1 4.68586726224E-04
<br>
3 3 1 -1.01851073716E-04
<br>
4 3 1 -5.60776424931E-04
<br>
1 4 1 -4.82771934254E-03
<br>
2 4 1 8.23931384971E-04
<br>
3 4 1 -5.60776424931E-04
<br>
4 4 1 1.92763112725E-04
<br>
1 1 2 -6.65118280325E-02
<br>
2 1 2 1.23351993366E-04
<br>
3 1 2 -1.01851073716E-04
<br>
4 1 2 8.23931384971E-04
<br>
1 2 2 8.23931384971E-04
<br>
2 2 2 2.34942628595E-04
<br>
3 2 2 2.34942628595E-04
<br>
4 2 2 8.23931384971E-04
<br>
1 3 2 4.68586726224E-04
<br>
2 3 2 2.34942628595E-04
<br>
3 3 2 -1.01851073716E-04
<br>
4 3 2 2.93469238677E-04
<br>
1 4 2 8.23931384971E-04
<br>
2 4 2 1.23351993366E-04
<br>
3 4 2 1.04562524785E-04
<br>
4 4 2 2.93469238677E-04
<br>
1 1 3 -5.60776424931E-04
<br>
2 1 3 -1.01851073716E-04
<br>
3 1 3 4.68586726224E-04
<br>
4 1 3 -4.82771934254E-03
<br>
1 2 3 -1.01851073716E-04
<br>
2 2 3 2.34942628595E-04
<br>
3 2 3 4.68586726224E-04
<br>
4 2 3 2.93469238677E-04
<br>
1 3 3 -1.01851073716E-04
<br>
2 3 3 -1.01851073716E-04
<br>
3 3 3 2.56886639370E-04
<br>
4 3 3 2.56886639370E-04
<br>
1 4 3 -5.60776424931E-04
<br>
2 4 3 1.04562524785E-04
<br>
3 4 3 2.56886639370E-04
<br>
4 4 3 2.93469238677E-04
<br>
1 1 4 -5.60776424931E-04
<br>
2 1 4 8.23931384971E-04
<br>
3 1 4 -4.82771934254E-03
<br>
4 1 4 1.92763112725E-04
<br>
1 2 4 1.23351993366E-04
<br>
2 2 4 8.23931384971E-04
<br>
3 2 4 2.93469238677E-04
<br>
4 2 4 1.04562524785E-04
<br>
1 3 4 -5.60776424931E-04
<br>
2 3 4 2.93469238677E-04
<br>
3 3 4 2.56886639370E-04
<br>
4 3 4 1.04562524785E-04
<br>
1 4 4 1.92763112725E-04
<br>
2 4 4 2.93469238677E-04
<br>
3 4 4 2.93469238677E-04
<br>
4 4 4 1.92763112725E-04
<br>
1 1 2 1
<br>
1 1 1 -6.65118280325E-02
<br>
2 1 1 -5.60776424931E-04
<br>
3 1 1 -5.60776424931E-04
<br>
4 1 1 -6.65118280325E-02
<br>
1 2 1 -4.82771934254E-03
<br>
2 2 1 1.92763112725E-04
<br>
3 2 1 -5.60776424931E-04
<br>
4 2 1 8.23931384971E-04
<br>
1 3 1 -4.82771934254E-03
<br>
2 3 1 -5.60776424931E-04
<br>
3 3 1 -1.01851073716E-04
<br>
4 3 1 4.68586726224E-04
<br>
1 4 1 -6.65118280325E-02
<br>
2 4 1 1.23351993366E-04
<br>
3 4 1 -1.01851073716E-04
<br>
4 4 1 8.23931384971E-04
<br>
1 1 2 -5.60776424931E-04
<br>
2 1 2 1.92763112725E-04
<br>
3 1 2 -4.82771934254E-03
<br>
4 1 2 8.23931384971E-04
<br>
1 2 2 1.92763112725E-04
<br>
2 2 2 1.92763112725E-04
<br>
3 2 2 2.93469238677E-04
<br>
4 2 2 2.93469238677E-04
<br>
1 3 2 -5.60776424931E-04
<br>
2 3 2 1.04562524785E-04
<br>
3 3 2 2.56886639370E-04
<br>
4 3 2 2.93469238677E-04
<br>
1 4 2 1.23351993366E-04
<br>
2 4 2 1.04562524785E-04
<br>
3 4 2 2.93469238677E-04
<br>
4 4 2 8.23931384971E-04
<br>
1 1 3 -5.60776424931E-04
<br>
2 1 3 -4.82771934254E-03
<br>
3 1 3 4.68586726224E-04
<br>
4 1 3 -1.01851073716E-04
<br>
1 2 3 -5.60776424931E-04
<br>
2 2 3 2.93469238677E-04
<br>
3 2 3 2.56886639370E-04
<br>
4 2 3 1.04562524785E-04
<br>
1 3 3 -1.01851073716E-04
<br>
2 3 3 2.56886639370E-04
<br>
3 3 3 2.56886639370E-04
<br>
4 3 3 -1.01851073716E-04
<br>
1 4 3 -1.01851073716E-04
<br>
2 4 3 2.93469238677E-04
<br>
3 4 3 4.68586726224E-04
<br>
4 4 3 2.34942628595E-04
<br>
1 1 4 -6.65118280325E-02
<br>
2 1 4 8.23931384971E-04
<br>
3 1 4 -1.01851073716E-04
<br>
4 1 4 1.23351993366E-04
<br>
1 2 4 8.23931384971E-04
<br>
2 2 4 2.93469238677E-04
<br>
3 2 4 1.04562524785E-04
<br>
4 2 4 1.23351993366E-04
<br>
1 3 4 4.68586726224E-04
<br>
2 3 4 2.93469238677E-04
<br>
3 3 4 -1.01851073716E-04
<br>
4 3 4 2.34942628595E-04
<br>
1 4 4 8.23931384971E-04
<br>
2 4 4 8.23931384971E-04
<br>
3 4 4 2.34942628595E-04
<br>
4 4 4 2.34942628595E-04
<br>
.......
<br>
.......
<br>
.......
<br>
<br>
Best
<br>
Md Jahid Hasan
<br>
PhD Student
<br>
University of Maine
<br>
<br>
_______________________________________________
<br>
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<br>
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<br>
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<br>
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<br>
</blockquote>
<br>
</blockquote>
<div class="moz-signature">-- <br>
<small>Dr. Lorenzo Paulatto<br>
IdR @ IMPMC - CNRS UMR 7590 & Sorbonne Université<br>
phone: +33 (0)1 442 79822 / skype: paulatz<br>
<a href="http://www.impmc.upmc.fr/~paulatto/"
class="moz-txt-link-freetext">http://www.impmc.upmc.fr/~paulatto/</a>
- <a href="https://anharmonic.github.io/"
class="moz-txt-link-freetext">https://anharmonic.github.io/</a><br>
23-24/423 B115, 4 place Jussieu 75252 Paris CX 05<small></small></small></div>
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