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<p>Good afternoon,</p>
<p style="text-align: justify;">For modeling purposes in the Quantum Espresso program (version 7.4.1), I want to create an input file scf.in that would include a supercell combining two materials with different crystal lattices – diamond (lattice parameter ibrav=2) and vertical graphene (lattice parameter ibrav=12), whose plane is perpendicular to the surface of the diamond. For the input file, I chose ibrav = 0 and a number of other parameters, which are presented below in the scf.in file. However, when viewing the resulting structure, which is shown as an image from the XCrySden program (version xcrysden-1.5.60-bin-semishared), I found a number of discrepancies between the stated number of carbon atoms (their total number in the ATOMIC_POSITIONS alat section is 24) and the number of atoms, which is greater than 30 and shown in the structure image. There are also other discrepancies.</p>
<p>Could you advise me on a possible solution to this problem?</p>
<p>Sincerely,</p>
<p>Valery Mishchenko</p>
<p>PhD, BSUIR</p>
<p>&control</p>
<p> calculation='scf',</p>
<p> prefix='gra',</p>
<p> verbosity= 'low',</p>
<p> pseudo_dir = './',</p>
<p> outdir='./',</p>
<p>/</p>
<p>&system</p>
<p> ibrav=0,</p>
<p> celldm(1)=6.64245</p>
<p> nbnd=48,</p>
<p> nat=24,</p>
<p> ntyp=1,</p>
<p> ecutwfc=40,</p>
<p>/</p>
<p>&electrons</p>
<p> conv_thr = 1d-06,</p>
<p>/</p>
<p>ATOMIC_SPECIES</p>
<p>C 12.011 C_ONCV_PBE-1.2.upf</p>
<p>CELL_PARAMETERS (alat)</p>
<p> 1.00 0.00 0.00</p>
<p> 0.00 2.00 0.00</p>
<p> 0.00 0.00 2.00</p>
<p>ATOMIC_POSITIONS alat</p>
<p> C 0.00 0.00 0.00</p>
<p> C 0.00 0.00 1.00</p>
<p> C 0.00 1.00 1.00</p>
<p> C 1.00 1.00 1.00</p>
<p> C 1.00 1.00 0.00</p>
<p> C 1.00 0.00 0.00</p>
<p> C 0.00 1.00 0.00</p>
<p> C 1.00 1.00 1.00</p>
<p> C 0.00 0.50 0.50</p>
<p> C 0.50 0.50 0.00</p>
<p> C 0.50 0.50 1.00</p>
<p> C 0.50 0.00 0.50</p>
<p> C 0.50 1.00 0.50</p>
<p> C 1.00 0.50 0.50</p>
<p> C 0.75 0.75 0.25</p>
<p> C 0.25 0.25 0.25</p>
<p> C 0.75 0.25 0.75</p>
<p> C 0.25 0.75 0.75</p>
<p> C 0.00 0.70 1.15</p>
<p> C 0.00 1.10 1.15</p>
<p> C 0.00 1.25 1.50</p>
<p> C 0.00 1.10 1.85</p>
<p> C 0.00 0.70 1.85</p>
<p> C 0.00 0.55 1.50</p>
<p>K_POINTS automatic</p>
<p>1 1 1 0 0 0</p>
<p><br /></p>
<p><br /></p>
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