<div dir="ltr"><div><div><div><div><div>Hello,<br><br></div>I'm confusing, I need to do some convergence test, but I don't know if I need primitive or one unit cell and how to select it.<br><br></div>I'm using this structure <a href="http://www.crystallography.net/cod/1513984.html">http://www.crystallography.net/cod/1513984.html</a><br><br></div>I extracted the crystallographic translation. The cell formula units are 8, has 56 atoms. See ATOMIC_POSITIONS bellow.<br><br>One unit cell of LiMn2O4 (spinel) has 7 atoms.<br></div><b><br></b></div>I have the following questions:<b><br></b><div><div><br><b><b>Do I need to put 7 atoms in the primitive cell or how many?<br><br></b>How can I select the atoms position for primitive or one unit cell?</b><br><br>ATOMIC_POSITIONS alat <br> Li 0.125000000 0.125000000 0.125000000 <br> Li -0.125000000 0.875000000 0.875000000 <br> Li 0.875000000 -0.125000000 0.875000000 <br> Li 0.875000000 0.875000000 -0.125000000 <br> Li -0.125000000 -0.125000000 -0.125000000 <br> Li -0.125000000 0.375000000 0.375000000 <br> Li 0.375000000 0.875000000 0.375000000 <br> Li 0.875000000 0.375000000 0.375000000 <br> Mn 0.500000000 0.500000000 0.500000000 <br> Mn -0.500000000 1.250000000 1.250000000 <br> Mn 1.250000000 -0.500000000 1.250000000 <br> Mn 1.250000000 1.250000000 -0.500000000 <br> Mn -0.500000000 -0.500000000 -0.500000000 <br> Mn 0.500000000 -0.250000000 -0.250000000 <br> Mn -0.250000000 0.500000000 -0.250000000 <br> Mn -0.250000000 -0.250000000 0.500000000 <br> Mn -0.500000000 0.750000000 0.750000000 <br> Mn 0.000000000 1.250000000 0.750000000 <br> Mn 0.000000000 0.750000000 1.250000000 <br> Mn 1.250000000 0.000000000 0.750000000 <br> Mn 0.750000000 -0.500000000 0.750000000 <br> Mn 0.750000000 0.000000000 1.250000000 <br> Mn 1.250000000 0.750000000 0.000000000 <br> Mn 0.750000000 1.250000000 0.000000000 <br> O -0.262700000 1.012700000 1.012700000 <br> O 1.012700000 -0.262700000 1.012700000 <br> O 1.012700000 1.012700000 -0.262700000 <br> O -0.262700000 -0.262700000 -0.262700000 <br> O 0.262700000 -0.012700000 -0.012700000 <br> O -0.012700000 0.262700000 -0.012700000 <br> O -0.012700000 -0.012700000 0.262700000 <br> O 0.262700000 0.262700000 0.262700000 <br> O -0.262700000 0.512700000 0.512700000 <br> O 0.237300000 1.012700000 0.512700000 <br> O 0.237300000 0.512700000 1.012700000 <br> O 1.012700000 0.237300000 0.512700000 <br> O 0.512700000 -0.262700000 0.512700000 <br> O 0.512700000 0.237300000 1.012700000 <br> O 1.012700000 0.512700000 0.237300000 <br> O 0.512700000 1.012700000 0.237300000 <br> O 0.512700000 0.512700000 -0.262700000 <br> O -0.262700000 0.237300000 0.237300000 <br> O 0.237300000 -0.262700000 0.237300000 <br> O 0.237300000 0.237300000 -0.262700000 <br> O 0.262700000 0.487300000 0.487300000 <br> O 0.762700000 -0.012700000 0.487300000 <br> O 0.762700000 0.487300000 -0.012700000 <br> O -0.012700000 0.762700000 0.487300000 <br> O 0.487300000 0.262700000 0.487300000 <br> O 0.487300000 0.762700000 -0.012700000 <br> O -0.012700000 0.487300000 0.762700000 <br> O 0.487300000 -0.012700000 0.762700000 <br> O 0.487300000 0.487300000 0.262700000 <br> O 0.262700000 0.762700000 0.762700000 <br> O 0.762700000 0.262700000 0.762700000 <br> O 0.762700000 0.762700000 0.262700000<br clear="all"><div><div><div><div><br>-- <br><div class="gmail_signature"><div>Máximo Ramírez<br></div><div>Physics Degree<br></div><div>Universidad Autónoma de Santo Domingo<br></div></div>
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