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<div class="moz-cite-prefix">Dear Alexader<br>
you are right that the vector separating two atoms includes
also the difference between their position inside the cell but
they are uniquely defined by this difference (well defined when
the two atoms are chosen) and a direct lattice vector R.<br>
this is the vector <span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
r(i) = (n1-1)*at(i,1)+(n2-1)*at(i,2)+(n3-1)*at(i,3) </span>we
are talking about.<br>
then the actual vector is computed as r_ws(i) = r(i) +
tau(i,na)-tau(i,nb)<br>
and its relation with respect to the WS super-cell of the
system is computed by wsweight(r_ws,rws,nrws)<br>
why the summation goes from -2*N to +2*N ? One wants to
include in the summation all the R that would lead to a point
inside the WS supercell. For a simple cubic lattice this would be
just from -N to N. For Bravais lattices with small angles between
the fundamental lattice vectors this is might not be enough.<br>
One could/should actually compute what is the safe range
needed include all relevant points... this was not done but we
just included a "VERY VERY SAFE RANGE!" of +/-2*N that proved safe
for all system examined so far.<br>
<br>
stefano<br>
<br>
<br>
On 11/07/2014 11:23 AM, Kvasov Alexander wrote:<br>
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<div class="WordSection1">
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Dear
Stefano,<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">thanks
a lot for your kind reply! One thing is still not clear for
me. Could you please clarify it? Please see below.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">>
the corresponding relevant real space vectors vectors
are therefore given by<br>
> r(i) =
(n1-1)*at(i,1)+(n2-1)*at(i,2)+(n3-1)*at(i,3) + their
periodic refolding to points nearest the origin
<br>
> a few examples should clarify:<br>
> 1 1 1 -> r = 0<br>
> 2 1 1 -> r = a1<br>
> 8 1 1 -> r = -a1<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><a moz-do-not-send="true"
name="_MailEndCompose"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">It’s
true for the same atoms, for example<o:p></o:p></span></a></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">8
8 8<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
1 1 1 1 (atom1=atom2=1)<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
1 1 1 5.72142674655E-02<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
2 1 1 -1.06343912107E-02<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
3 1 1 1.01649714042E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
4 1 1 4.15611567060E-06<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
5 1 1 -6.46046533014E-06<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
6 1 1 4.15611567060E-06<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
7 1 1 1.01649714042E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
8 1 1 -1.06343912107E-02<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">and
indeed<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">1
1 1 -> r = 0<br>
2 1 1 -> r = a1<br>
8 1 1 -> r = -a1<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">However,
if we take
<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> 3
5 0 7.3434758 0.0000000 0.0000000 0.0000000 0.0000000
0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
1.000000000 0.000000000 0.000000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.000000000 1.000000000 0.000000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.000000000 0.000000000 1.000000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
1 'Sr ' 79860.7444956297
<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> 2
'Ti ' 43628.1015381455
<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> 3
'O ' 14582.5610075711
<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> 1
1 0.0000000000 0.0000000000 0.0000000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
2 2 0.5000000000 0.5000000000 0.5000000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
3 3 0.5000000000 0.5000000000 0.0000000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
4 3 0.5000000000 0.0000000000 0.5000000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
5 3 0.0000000000 0.5000000000 0.5000000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">T<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
6.2439081 0.0000000 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 6.2439081 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 0.0000000 6.2439081<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
1<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
2.4363133 0.0000000 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 2.4363133 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 0.0000000 2.4363133<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
2<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
7.3260124 0.0000000 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 7.3260124 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 0.0000000 7.3260124<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
3<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
-2.0082996 0.0000000 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 -2.0082996 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 0.0000000 -5.7457266<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
4<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
-2.0082996 0.0000000 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 -5.7457266 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 0.0000000 -2.0082996<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
5<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
-5.7457266 0.0000000 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 -2.0082996 0.0000000<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
0.0000000 0.0000000 -2.0082996<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
8 8 8<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">…..<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">…..<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
1 1 1 2 (<b>atom1(atom of origin)=2,
atoms2=1</b>)<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
1 1 1 -1.52661521097E-03<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
2 1 1 -1.52661520884E-03<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
3 1 1 -2.40826237874E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
4 1 1 -1.56748657082E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
5 1 1 -9.53993420913E-05<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
6 1 1 -9.53993442291E-05<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
7 1 1 -1.56748429042E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
8 1 1 -2.40826009834E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">and
R-R0 is not anymore (n1-1)*a+(n2-1)*b+(n3-1)*c, but should
include difference between atoms like<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">R-R0=(n1-1)*a+(n2-1)*b+(n3-1)*c+(
R_cell(atom1) – R_cell(atom2))<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">this
way
<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> 1
1 1 -1.52661521097E-03 R-R0=-a/2<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
2 1 1 -1.52661520884E-03 R-R0= a/2<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
3 1 1 -2.40826237874E-04 R-R0= 3a/2<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
4 1 1 -1.56748657082E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
5 1 1 -9.53993420913E-05<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
6 1 1 -9.53993442291E-05<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
7 1 1 -1.56748429042E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
8 1 1 -2.40826009834E-04 R-R0=-3a/2<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Moreover
in SUBROUTINE frc_blk i don’t find the place where the
difference between atoms is taken into account<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">…<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">r(i)
= n1*at(i,1)+n2*at(i,2)+n3*at(i,3)<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"
lang="FR-CH">…<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"
lang="FR-CH">arg = tpi*(q(1)*r(1) + q(2)*r(2) + q(3)*r(3))<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"
lang="FR-CH">
</span><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">DO
ipol=1, 3<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
DO jpol=1, 3<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
dyn(ipol,jpol,na,nb) = &<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
dyn(ipol,jpol,na,nb) + &<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
(frc(m1,m2,m3,ipol,jpol,na,nb)+f_of_q(ipol,jpol,na,nb))
&<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
*CMPLX(COS(arg),-SIN(arg),kind=DP)*weight<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">…<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">another
small question why in SUBROUTINE frc_blk the summation goes
from -2N to 2N ???<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
DO n1=-2*nr1,2*nr1<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
DO n2=-2*nr2,2*nr2<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
DO n3=-2*nr3,2*nr3<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Alexander<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">From:
<a class="moz-txt-link-abbreviated" href="mailto:pw_forum-bounces@pwscf.org">pw_forum-bounces@pwscf.org</a>
[<a class="moz-txt-link-freetext" href="mailto:pw_forum-bounces@pwscf.org">mailto:pw_forum-bounces@pwscf.org</a>] On Behalf Of stefano de
gironcoli<br>
Sent: 06 November 2014 18:55<br>
To: PWSCF Forum<br>
Subject: Re: [Pw_forum] IFCs and supercell<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">dear
Alexander,<br>
<br>
the grid correspond to a 8x8x8 supercell (or rather to
the FFT of a 8x8x8 q-point grid ... which is the same)
<br>
<br>
atomic pairs are specified by the indices of the two
atoms in the unit cell plus the direct lattice vector
connecting the two cells in which they are located with two
important details to be considered<br>
1) the origin is the 1,1,1 element of the list<br>
2) the IFC are obtained by a FFT from the dynamical
matrices of the q-point grid and are therefore written
assuming 8 8 8 periodicity (in the present case)<br>
the corresponding relevant real space vectors vectors
are therefore given by<br>
r(i) = (n1-1)*at(i,1)+(n2-1)*at(i,2)+(n3-1)*at(i,3) +
their periodic refolding to points nearest the origin
<br>
a few examples should clarify:<br>
1 1 1 -> r = 0<br>
2 1 1 -> r = a1<br>
8 1 1 -> r = -a1<br>
<br>
the routine weight play the fundamental role of
trimming the vector in such a way the only the points inside
the wigner-seitze<br>
cell of the supercell contribute<br>
weight (r) = 1 if r is inside the WS cell<br>
weight (r) = 0 if r is ouside the WS cell<br>
weight (r) = 1/(n+1) if r is on the surface of the WS
cell where n is the number of planes that pass through it<br>
<br>
stefano<br>
<br>
On 11/06/2014 06:14 PM, Kvasov Alexander wrote:<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Dear
All,<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">My
question is: how the supercell (which is used by q2r and
matdyn) is specified? If anybody has any information about
this I would highly appreciate.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">“fltau”
option of matdyn gives atomic positions only for 1 cell and
not for N1xN2xN3 supercell.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Apparently,
there are some tricks… for example, here one has some IFCs
for 8x8x8 grid of SrTiO3<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">...<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
8 8 8<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
1 1 1 1<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
1 1 1 5.72142674655E-02<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
2 1 1 -1.06343912107E-02<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
3 1 1 1.01649714042E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
4 1 1 4.15611567060E-06<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
5 1 1 -6.46046533014E-06<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
6 1 1 4.15611567060E-06<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
7 1 1 1.01649714042E-04<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
8 1 1 -1.06343912107E-02<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">...<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">1.
first, IFC values decries with N1 and then increase, so they
have to be shuffled<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">2.
second, it seems SUBROUTINE setupmat and frc_blk is the
right place to look for this<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">…<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">DO
na=1, nat<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
DO nb=1, nat<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
total_weight=0.0d0<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
DO n1=-2*nr1,2*nr1<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
DO n2=-2*nr2,2*nr2<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
DO n3=-2*nr3,2*nr3<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
!<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
! SUM OVER R VECTORS IN THE SUPERCELL - VERY VERY SAFE
RANGE!<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
!<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
DO i=1, 3<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
r(i) = n1*at(i,1)+n2*at(i,2)+n3*at(i,3)<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">
END DO<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">…<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">but
summation goes from -2N to 2N, which is not clear for me.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">3.
what is “weight” in SUBROUTINE setupmat and frc_blk<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">If
anybody could explain what is going on here it would be
great!<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Sincerely
yours,<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Alexander
Kvasov<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Scientist<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Ceramics
Laboratory (LC)<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"
lang="FR-CH">École Polytechnique Fédérale de Lausanne (EPFL)<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"
lang="FR-CH"> <o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Phone:
+41 21 693 5805<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Address:<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">EPFL
STI IMX LC<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">MXD
220 (Bâtiment MXD) Station 12<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">1015
Lausanne, Switzerland<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"> <o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black"><br>
<br>
<br>
<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria",serif;color:black">_______________________________________________<o:p></o:p></span></p>
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style="font-size:12.0pt;font-family:"Cambria",serif;color:black">Pw_forum
mailing list<o:p></o:p></span></p>
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