[Wien] Role of sgroup program
Dear Peter Blaha WIEN2k users, I am using WIEN2k 12.1 version. During initialization through w2web while viewing outputsgroup we can accept either the case.struct file generated by sgroup (which changes the position coordinates of the atoms in the primitive cell) or keep our original file. According to UG default is the latter one. Does they both refer to same structure? For TiC both cases run without error. Does the properties calculated from both structure file should be same? For some complicated compunds e.g. spinel compounds #227 fd-3m, we have to accept the struct file generated by sgroup to run an error free SCF. It changes the position coordinates of the atoms in the primitive cell whose original input was origin choice 2 of space group fd-3m .Does it still refer to the same structure but with a different primitive cell Thanks in advance, with regards, Saurabh Samanta ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
Re: [Wien] Role of sgroup program
Hello Saurabh, Sgroup will try to find the smallest primitive cell by maximizing the symmetry. This gives you the same structure. Since this lowers the amount of inequivalent positions it does reduce the freedom (so if you want to give one of them a slight nudge and break the symmetry you may not be able to do that within the higher symmetrical spacegroup). You should also make sure the struct files you are feeding into sgroup have sufficient decimals in their positions for instance a position at 1/3 may not be recognised when you feed sgroup 0.3330 but will be recognized 0.33 which may affect the output structure. You may wish to give us some more information on those errors you get if you don't switch to the sgroup-generated struct though since that does not seem normal to me in first instance. Regards, Michael Sluydts Op 24/06/2013 10:43, saurabh samant schreef: Dear Peter Blaha WIEN2k users, I am using WIEN2k 12.1 version. During initialization through w2web while viewing outputsgroup we can accept either the case.struct file generated by sgroup (which changes the position coordinates of the atoms in the primitive cell) or keep our original file. According to UG default is the latter one. Does they both refer to same structure? For TiC both cases run without error. Does the properties calculated from both structure file should be same? For some complicated compunds e.g. spinel compounds #227 fd-3m, we have to accept the struct file generated by sgroup to run an error free SCF. It changes the position coordinates of the atoms in the primitive cell whose original input was origin choice 2 of space group fd-3m .Does it still refer to the same structure but with a different primitive cell Thanks in advance, with regards, Saurabh Samanta ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
Re: [Wien] Role of sgroup program
Some spacegroup have 2 different settings (the origin of the cell is shifted to another position). Wien2k requires a setting WITH inversion symmetry at the origing and sgroup will do this for you in case of a spinel-structure. Other structures do not have this problem with settings and it is not necessary to follow sgroup, except when it would reduce the unitcell size (making it eg. 16 atoms instead of 64, ...) On 06/24/2013 10:43 AM, saurabh samant wrote: Dear Peter Blaha WIEN2k users, I am using WIEN2k 12.1 version. During initialization through w2web while viewing outputsgroup we can accept either the case.struct file generated by sgroup (which changes the position coordinates of the atoms in the primitive cell) or keep our original file. According to UG default is the latter one. Does they both refer to same structure? For TiC both cases run without error. Does the properties calculated from both structure file should be same? For some complicated compunds e.g. spinel compounds #227 fd-3m, we have to accept the struct file generated by sgroup to run an error free SCF. It changes the position coordinates of the atoms in the primitive cell whose original input was origin choice 2 of space group fd-3m .Does it still refer to the same structure but with a different primitive cell Thanks in advance, with regards, Saurabh Samanta ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html -- P.Blaha -- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 Email: bl...@theochem.tuwien.ac.atWWW: http://info.tuwien.ac.at/theochem/ -- ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien SEARCH the MAILING-LIST at: http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
