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Hi all,</div>
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I am trying to figure out whether there is a way to scale all three unit cell vectors at once in QE using pw.x. In my input file, I am using the CELL_PARAMETERS card (in units of Angstrom) to specify a unit cell. This (<a href="https://www.mail-archive.com/users@lists.quantum-espresso.org/msg19387.html" style="">https://www.mail-archive.com/users@lists.quantum-espresso.org/msg19387.html</a>)
old post seems to suggest that the 'A' parameter in the &SYSTEM section acts as a scaling parameter if 'ibrav==0' and the CELL_PARAMETERS card is used to specify the lattice. I take this to mean that each lattice vector is multiplied by *A, where A is a dimensionless
number. However, QE complains that:</div>
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"<span>Error in routine cell_base_init (2):<br>
</span><span> lattice parameter specified twice"</span></div>
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I've tried specifying the atomic positions in 'crystal' (fractional) coordinates and in Angstroms but to no use. Input file is attached below. I'm using QE version 6.4.1.</div>
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<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">Is the interpretation of A as a scaling parameter with these settings deprecated, or am I missing something?</span></div>
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<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">Thanks in advance,</span></div>
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<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">Siebe</span></div>
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<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">input file:</span></div>
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<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;"><span style="font-family: "Courier New", monospace;"> &CONTROL</span><span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> title = 'cha' ,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> calculation = 'scf' ,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> wf_collect = .true. ,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> etot_conv_thr = 1.0D-6 ,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> /</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> &SYSTEM</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> ibrav = 0,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> A = 1.2,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> nat = 108,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> ntyp = 2,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> ecutwfc = 100 ,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> nosym = .true. ,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> /</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> &ELECTRONS</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> scf_must_converge = .true. ,</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> /</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;">CELL_PARAMETERS angstrom</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> 13.738516409 -0.000070574 0.000007978</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> -6.869319180 11.897869408 -0.000009602</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> 0.000010055 -0.000007302 14.715552482</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;">ATOMIC_SPECIES</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> O 15.99940 O.pbe-rrkjus.UPF</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;"> Si 28.08551 Si.pbe-rrkj.UPF</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;">ATOMIC_POSITIONS crystal</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;">O 0.901932010 0.098069851 0.126854702</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;">O 0.098068745 0.901933544 0.873144107</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;">O 0.901940529 0.803877937 0.126862649</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;">O 0.098062465 0.196127742 0.873139246</span><br>
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<div dir="ltr" style="text-align: left;"><span style="font-family: "Courier New", monospace;">(...)</span></div>
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<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;"><span></span></span><span style="font-family: "Courier New", monospace; font-size: 12pt;">K_POINTS gamma</span></div>
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