<div><br></div><div>The problem is with the symmetry of the supercell you created. You must have chosen 2x1x1 or 1x1x2 supercell here. So you need to remember that after doubling the lattice parameters, the space group and point group symmetries also changes. It means that while doing "sgroup" during initialization the program will find new spacegroup (which is not 225 anymore), and the wyckoff positions of the atoms in your unitcell will be classified under that spacegroup. That is why the multiplicity changes. Its of no harm to accept it as Prof Blaha suggested, or else you can rename all atoms with different index and can continue with space group P1 ( your multiplicity all other stuff will remain unchanged in that case). </div>
<br clear="all"><div><font color="#009900" face="georgia, serif">Prasenjit Roy</font><div><font color="#009900" face="georgia, serif">Electronic Structures of Materials</font></div><div><font color="#009900" face="georgia, serif">Radboud University</font></div>
<div><font color="#009900" face="georgia, serif">Nijmegen</font></div><div><font face="georgia, serif"><span style="font-size:12px;background-color:rgb(255,255,255)"><font color="#ff0000">+</font><font color="#009900">31 (0) 24 36 </font></span><span style="color:rgb(0,153,0);background-color:rgb(255,255,255);font-size:12px">52805</span></font></div>
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