Dear Kumar, The message is just warning for you, a signal, be sure that your structure is correct. This prevents adding? additional nonfractional translations. So, it is OK, if you really use a supercell.
And this is very likely as according to http://cst-www.nrl.navy.mil/lattice/struk/aO2.html alpha-O2 is a? base-centered monoclinic lattice with 2 atoms in the unit cell, but? you used simple monoclinic with 4 atoms, that is why you got such kind message. Bests, Eyvaz. ------------------------------------------------------------------- Prof. Eyvaz Isaev, Department of Physics, Chemistry, and Biology (IFM), Linkoping University, Sweden Theoretical Physics Department, Moscow State Institute of Steel & Alloys, Russia, isaev at ifm.liu.se, eyvaz_isaev at yahoo.com --- On Thu, 8/12/10, sonu kumar <1009ukumar at gmail.com> wrote: From: sonu kumar <[email protected]> Subject: [Pw_forum] This is a supercell, fractional translation are disabled ? To: pw_forum at pwscf.org Date: Thursday, August 12, 2010, 4:35 PM Dear All QE users, While doing scf calculations on alpha O2 crystal, i got a massage : Found symmetry operation: I + (? 0.0000 -0.5000 -0.5000) ???? This is a supercell, fractional translation are disabled Although code correctly predicts the space group, is there something wrong in the input coordinates? However, i checked the structure in Xcrysden, and found it to be correct (i.e. correct bond lengths, angles, distances between atoms). Can anybody help me out? Below is the part of input file: ################################################################# &system ??? ibrav = 12, ??? celldm(1)=9.5860, celldm(2)=1.06271, celldm(3)=0.67699, celldm(4)=-0.672625 ??? nat=4, ntyp=1,???????????? ??? nbnd=12,?????????????????? ??? ecutwfc=40,????????????????? ??? ecutrho=300,????????????? ?/ ATOMIC_SPECIES ?O??? 8.0000 O.pbe-van_ak.UPF?? ATOMIC_POSITIONS (crystal) O? 0.171000? 0.105000 0.000000 O -0.171000 -0.105000 0.000000 O? 0.171000? 0.605000 0.500000 O -0.171000? 0.395000 0.500000 ################################################################# With Kind Regards, Sonu Kumar Phd Student Physics Department Indian Institute of Technology Delhi-110016, India web:-http://www.iitd.ac.in/ -----Inline Attachment Follows----- _______________________________________________ Pw_forum mailing list Pw_forum at pwscf.org http://www.democritos.it/mailman/listinfo/pw_forum -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20100812/d71c3c87/attachment.htm
