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Hello, I am new to quantum espresso and currently using QE 6.1<div><br></div><div>I have run QE for several weeks, and have no problem running examples and new materials. But one thing I still can not figure out is the crystal structure part of pw input file.</div><div><br></div><div>To be more specific, I don't know how to make crystal_sg work. There are few posts on wyckoff position and crystal_sg on this forum, but all lack some detail. What I need is some examples, for example simple Silicon, ZnS, etc that described using crystal_sg.</div><div><br></div><div>I tried below for silicon</div><div><br></div><div>!---------------------------</div><div><div>&CONTROL</div><div>prefix='silicon',</div><div>calculation = 'scf' ,</div><div>/</div><div>&SYSTEM</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>ibrav = 2,celldm(1) = 10.263,nat = 1,ntyp = 1,</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>ecutwfc = 44.,ecutrho = 175.,</div><div>ATOMIC_SPECIES</div><div>Si 28.0855 Si.pbe-n-rrkjus_psl.1.0.0.UPF</div><div>ATOMIC_POSITIONS crystal_sg</div><div>Si 8a</div><div>K_POINTS automatic</div><div>10 10 10 1 1 1</div></div><div>!-----------------------------</div><div><br></div><div>However, xcrysden shows error when opening this input file.</div><div><br></div><div>Also actually, I don't quite understand wyckoff position after reading some web pages and how to use this database on site <a href="http://www.cryst.ehu.es/cgi-bin/cryst/programs/nph-wp-list?gnum=227&gor=1">http://www.cryst.ehu.es/cgi-bin/cryst/programs/nph-wp-list?gnum=227&gor=1</a> to write input file in crystal_sg form. Could somebody explain it?</div><div><br></div><div><br></div><div><div><br></div><div><br></div></div><!--😀-->
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