<span style="font-size: 12pt; line-height: 200%; font-family: "Times New Roman";">It is generally believed that the on-site Coulomb repulsion U integral as an input parameter for the LDA+U calculations depends on the system under study, and can vary for an atom from one case to the others. Furthermore, the value obtained for the U parameter depends on the method of calculations.<br> Thus one can first calculate a suitable U value for each case using the method discussed by Anisiomov 91 (PRB). An alternative way is to vary the U value in a proper interval to find the most appropriate one comparing the theoretically calculated results with the experiment.<br> <br> It is mandatory to set the U value (effective one,i.e. U-J) for each nonequivalent atoms. But I see in your struct file you have two equivalent Ti atoms. Hence for your case only one U_effective is necessary in your inorb file.<br> </span><br><b><i>°×Óî
<baiyu1982@ss.buaa.edu.cn></i></b> wrote:<blockquote class="replbq" style="border-left: 2px solid rgb(16, 16, 255); margin-left: 5px; padding-left: 5px;"> Dear Wien users:<br>Recently I had done some caculation about anatase TiO2 using LDA+U method. I followed Anisimov's way that add a 6eV potential<br>to Ti 3d orbit. But I could not get the correct result like his caculation which have a 3.2eV bandgap, while I have only 2.8eV.<br>Since he is using the LCAO basis, I wondered whether his U=6eV is suitable for out LAPW basises? Major input file is listed below.And at the same time I want to know whether the two Ti atoms in struct file which all have the same atom index have been added with the orb potential?<br>Please give me some suggestions on how i can get a more desirable result like a 3.2 eV bandgap?<br><br>PS: my SCF is ran under -ec 0.00005. Is the covergence too large?<br><br><br>anatase<br>B LATTICE,NONEQUIV.ATOMS: 2141_I41/amd<br>MODE OF CALC=RELA
unit=bohr<br> 7.223948 7.223948 18.164868 90.000000 90.000000 90.000000<br>ATOM -1: X=0.00000000 Y=0.25000000 Z=0.87500000<br> MULT= 2 ISPLIT=-2<br> -1: X=0.00000000 Y=0.75000000 Z=0.12500000<br>Ti NPT= 781 R0=0.00005000 RMT= 1.8000 Z: 22.0<br>LOCAL ROT MATRIX: 0.7071068-0.7071068 0.0000000<br> 0.7071068 0.7071068 0.0000000<br> 0.0000000 0.0000000 1.0000000<br>ATOM -2: X=0.00000000 Y=0.25000000 Z=0.08271596<br> MULT= 4 ISPLIT= 8<br> -2: X=0.00000000 Y=0.75000000 Z=0.91728404<br> -2: X=0.00000000 Y=0.75000000 Z=0.33271596<br> -2: X=0.50000000 Y=0.75000000 Z=0.16728404<br>O NPT= 781 R0=0.00003000 RMT= 1.6000 Z: 8.0<br>LOCAL ROT MATRIX: 1.0000000 0.0000000 0.0000000<br> 0.0000000 1.0000000 0.0000000<br> 0.0000000 0.0000000 1.0000000<br> 16 NUMBER OF SYMMETRY
OPERATIONS<br>******************************************************************<br>indm:<br>-9. Emin cutoff energy<br> 1 number of atoms for which density matrix is calculated<br> 1 1 2 index of 1st atom, number of L's, L1<br> 0 0 r-index, (l,s)index<br>*********************************************************************<br>inorb:<br> 1 1 0 nmod, natorb, ipr<br>PRATT 1.0 BROYD/PRATT, mixing<br> 1 1 2 iatom nlorb, lorb<br> 1 nsic 0..AFM, 1..SIC, 2..HFM<br> 0.44 0.01 U J (Ry)<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><BR><BR>Sincerely yours,<br>S. Jalali.<br>/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/<br>Saeid Jalali Asadabadi,<br>Department of
Physics, Faculty of Science,<br>University of Isfahan (UI), Hezar Gerib Avenue,<br>81744 Isfahan, Iran.<br>Phones:<br>Dep. of Phys. :+98-0311-793 2435<br>Office :+98-0311-793 2430<br>Fax No. :+98-0311-793 2409<br>E-mail :s_jalali_a@yahoo.com<br>www :http://www.ui.ac.ir<br>/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/<p> 
<hr size=1>Groups are talking. We´re listening. Check out the <a href="http://pa.yahoo.com/*http://us.rd.yahoo.com/evt=41144/*http://groups.yahoo.com/local/newemail.html">handy changes to Yahoo! Groups.</a>