<DIV class=MsoPlainText style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="mso-fareast-font-family: 'MS Mincho'"><FONT face="Courier New">Hi Michael and all wien users,<BR><BR>Thanks for your suggestion.<BR>I have tried to generate Al2O3 supercell in Wien by following your suggestion. But yet,I have not got proper result.</FONT></SPAN></DIV> <DIV class=MsoPlainText style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="mso-fareast-font-family: 'MS Mincho'"><FONT face="Courier New">The structure files are attached.<BR>(1)File a.struct : Using Wyckoffpositions (4 Al & 6 O) but without adding transformation<SPAN style="mso-spacerun: yes"> : lattice type selected :H </SPAN><SPAN style="mso-spacerun:
yes"> </SPAN><BR>Derived space group:193(P 63/mcm)and not the required 167R3cH</FONT></SPAN></DIV> <DIV class=MsoPlainText style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="mso-fareast-font-family: 'MS Mincho'"><FONT face="Courier New"><BR>(2) File a2.struct : Wycoff position with added transformation: (2/3,1/3,1/3)+ -Al<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p></FONT></SPAN></DIV> <DIV class=MsoPlainText style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-GB style="mso-fareast-font-family: 'MS Mincho'"><FONT face="Courier New">(1/3,2/3,2/3)+ -O<BR>Lattice type selected : H<SPAN style="mso-spacerun:
yes"> </SPAN><BR>Derived space group :1 P1</FONT></SPAN></DIV><SPAN lang=EN-GB style="mso-fareast-font-family: 'MS Mincho'"><FONT face="Courier New"> <DIV class=MsoPlainText style="MARGIN: 0cm 0cm 0pt"><BR>(3)File A_latest.struct : Putting all 30 positions with added transformation :<BR>Lattice selected :P<SPAN style="mso-spacerun: yes"> </SPAN></DIV> <DIV class=MsoPlainText style="MARGIN: 0cm 0cm 0pt"><SPAN style="mso-spacerun: yes">Derived space group : 15 (C 2/c)</SPAN></DIV> <DIV class=MsoPlainText style="MARGIN: 0cm 0cm 0pt"><SPAN style="mso-spacerun: yes"></SPAN>In no process my required space group is derived, ie 167 R-3c:H <BR>What can I do now? Please help me.</DIV> <DIV class=MsoPlainText style="MARGIN: 0cm 0cm 0pt">Swati</FONT><BR></DIV></SPAN><BR><B><I>Michael
Fischer <dommiguel@gmx.de></I></B> wrote: <BLOCKQUOTE class=replbq style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">Hello,<BR><BR>sorry, I was not aware that you cannot select the space group in <BR>hexagonal setting in structgen - as I said, I do not have much <BR>experience with rhombohedral and hexagonal cells in WIEN2k.<BR><BR>I think you should do as follows: Choose H lattice type and enter the <BR>atoms separately. You have to enter 4 aluminium and 6 oxygen positions. <BR>The other ones should be generated by the lattice type. In order to <BR>find out which positions you need to enter, I suggest you use "WYCKPOS" <BR>of www.cryst.ehu.es. There, you enter space group 167 and look at the <BR>coordinates given for Wyckoff positions 12c (Al) and 18e (O). For x or <BR>z, you substitute the coordinate you have calculated.<BR>E.g. for Al at the position (0 0 0.35), i.e. z=0.35, you need to enter <BR>the four positions:<BR>0 0 0.35<BR>0 0
0.15<BR>0 0 0.85<BR>0 0 0.65<BR>Alternatively, select P lattice type and enter all 12 and 18 atoms <BR>respectively (more tedious). In addition to the above, you need to <BR>apply the transformations for all four Al and six O-positions.<BR>(2/3,1/3,1/3) +<BR>(1/3,2/3,2/3) +<BR><BR>The cause why your second try did not work is easily explained: If you <BR>enter only two atoms and do not choose the correct space group, <BR>structgen does not know how to generate the symmetry-equivalent atoms. <BR>So you end up with a cell that has way too few atoms.<BR><BR>Greetings<BR>Michael<BR><BR>_______________________________________________<BR>Wien mailing list<BR>Wien@zeus.theochem.tuwien.ac.at<BR>http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien<BR></BLOCKQUOTE><BR>