[Wien] Fwd: A question regarding unusual DOS pattern
-- Forwarded message -- From: shamik chakrabarti List-Post: wien@zeus.theochem.tuwien.ac.at Date: Thu, Jul 12, 2012 at 3:43 AM Subject: A question regarding unusual DOS pattern To: A Mailing list for WIEN2k users Dear wien2k users, We have simulated DOS of a Li based oxide material. Although, there is band gap across Fermi energy for atomic DOS of transition metal atom presents in the alloy, atomic DOS of Li is significant and continuous across Ef. It seems from the total DOS and atomic DOS of Li that the alloy can behave as a half metal due (DOS is connected from valance band to conduction band through spin dn channel) to Li atom which should be wrong. However, from the total energy calculation we have calculated Li intercalation voltage which is matching very closely with experimental value (with a 200 mV overestimation which is considered to be small in this type of calculation). This calculation was done using experimental structural parameters and without doing geometrical optimization due to presence of large number of atoms in the unit cell. *There is also large force appearing on the Li atoms (around 100 mRy/a.u.). However, again I insist on the fact that the Li intercalation voltage from the same calculation giving very accurate value. * My question is: (1) Whether the appearance of Li DOS across Fermi energy may have its origin in the fact of not having done the geometrical optimization which is the cause of strained Li-O bond? (2) OR appearing of Li DOS across Ef may consist of some different Physics? It is true that we may tell the answer properly after doing the geometrical optimization...but before starting that huge job (!)...any response in this regard will be very helpful for us. Thanking you, -- Shamik Chakrabarti Senior Research Fellow Dept. of Physics & Meteorology Material Processing & Solid State Ionics Lab IIT Kharagpur Kharagpur 721302 INDIA -- Shamik Chakrabarti Senior Research Fellow Dept. of Physics & Meteorology Material Processing & Solid State Ionics Lab IIT Kharagpur Kharagpur 721302 INDIA -- next part -- An HTML attachment was scrubbed... URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20120716/177864b5/attachment.htm>
[Wien] Virual Crystal and Supercell
The VCA is not very reliable for such a problem, where the "mixed" elements have "active" electrons at/near EF. One can use the VCA for elements which dope a system with electrons (or holes) like eg. in ionic compounds (eg. some oxides) with Ba/La or K/Ca ..., where these elements do not participate much in the chemical bonding between eg. a Transition metal and oxygen. The "supercell" approach has the disadvantage of spurious "ordering" effects, thus one should use large enough supercells and test various distributions of the dopants to see its effect. But for a Cu/Zn system it is definitely the better approach. For DOS properties of metallic alloys the cpa is a fairly good approximation, but this is not available in wIEN2k (and you do not learn anything about local relaxations,...) Am 13.07.2012 00:29, schrieb prasenjit roy: > Dear Wien2K Users, > I want to use virtual crystal > approximation(VCA) for a very large system, so I applied it on a simple > system [Ni(28)] to check whether everything is correct or not. To do > that, I did the following steps. > 1. Initialized the calculation with Ni(Z=28). > 2. Changed Z to 28.15 > 3. Changed case.inst to: > -- > Ni > Ar 3 > 3, 2,2.00 N > 3, 2,2.00 N > 3,-3,3.00 N > 3,-3,1.30 N > 4,-1,1.00 N > 4,-1,0.85 N > > > --- > 4. Changed NE in case.in2* from 16 to 16.15 > 5. Run the spin polarized calculation. > I also did a supercell calculation where > the 2x2x2 supercell was containing 32 non equivalent Ni atoms. Then, I > replaced 5 of them with Cu (Z=29) to make a 15% doped system. Next "x > spacegroup" changed the spacegroup and reduced the number of symmetry > operations. At last the scf calculation was performed and solution > converged. > The problem is, the density of states is > reasonably different in these two above described cases. The density > obtained from the VCA looks almost like the pure Ni DOS. Whereas that > obtained from supercell approach is different. I need to know whether > the ways of approach are correct or not in both cases. Should I consider > the supercell approach more reliable over the VCA ? While constructing a > supercell, is it needed to increase the number of k points also ? > Thank you very much in advance for helping me. > > Prasenjit Roy > Radboud University, Nijmegen > > > ___ > Wien mailing list > Wien at zeus.theochem.tuwien.ac.at > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien > -- Peter Blaha Inst.Materials Chemistry TU Vienna Getreidemarkt 9 A-1060 Vienna Austria +43-1-5880115671
[Wien] lapwdm angle.f
Thank's for the hint for angle.f in SRC_lapwdm. Yes, I think the same fix should be applied to this program. (Apparently both routines did not support a triclinic lattice). The "logic" of these "if statements" should be such that the first case handles a monoclinic lattice with angle gamma .ne. 90 (and the others are 90) the second with beta.ne.90 the third case handles a triclinic lattice. And yes, you are absolutely right, in the fix is a stupid misstype. It should be: ELSE IF ((ABS(ALPHA(2)-PI/2.d0).GT.1.D-4).and.(ABS(ALPHA(1)-PI/2.d0).LT.1.D-4).and.(ABS(ALPHA(3)-PI/2.d0).LT.1.D-4)) THEN ^ PS: I'm not sure if all this is really necessary or one could stick to the last general formulae. PPS: I'd like to thank you explicitly for your many valuable comments to the mailing list in the last months. Thank you very much !!! Am 02.07.2012 00:56, schrieb Gavin Abo: > Dear Dr. Blaha and developers, > > Fixes to angle.f in SRC_qtl was reported: > > http://zeus.theochem.tuwien.ac.at/pipermail/wien/2012-June/017085.html > > It suggested changes to the if statements. > * > IF (ABS(ALPHA(3)-PI/2.d0).GT.1.D-4) THEN* > > to > > *IF > ((ABS(ALPHA(3)-PI/2.d0).GT.1.D-4).and.(ABS(ALPHA(2)-PI/2.d0).LT.1.D-4).and.(ABS(ALPHA(1)-PI/2.d0).LT.1.D-4)) > THEN* > > and > > *ELSE IF (ABS(ALPHA(2)-PI/2.d0).GT.1.D-4) THEN* > > to > > *ELSE IF > ((ABS(ALPHA(2)-PI/2.d0).GT.1.D-4).and.(ABS(ALPHA(1)-PI/2.d0).LT.1.D-4).and.(ABS(ALPHA(2)-PI/2.d0).LT.1.D-4)) > THEN* > > The angle.f in SRC_lapwdm is almost the same. Should these fixes be applied > to it too? > > Can you confirm that the absolute values such as on > "ABS(ALPHA(3)-PI/2.d0).GT.1.D-4" are correct? It may be correct, but it looks > suspicious to me. The left side argument will > always be positive because of the absolute value. Therefore, the if > statements may never have a different result (true or false) unless the left > argument is almost zero. > > P.S., Kateryna, your ORBxxx and SPIxxx results might change if a fix is > needed. However, that is only if the code needs to select a different set of > crystal geometry equations in > angle.f for your crystal structure instead of: > > IF (ABS(ALPHA(3)-PI/2.d0).GT.1.D-4) THEN > XA=XMS(1)*AA*SIN(ALPHA(3)) > XB=XMS(1)*AA*COS(ALPHA(3))+BB*XMS(2) > XC=CC*XMS(3) > > Kind Regards, > > Gavin Abo > > > ___ > Wien mailing list > Wien at zeus.theochem.tuwien.ac.at > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien > -- P.Blaha -- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 Email: blaha at theochem.tuwien.ac.atWWW: http://info.tuwien.ac.at/theochem/ -- -- next part -- A non-text attachment was scrubbed... Name: angle.f Type: text/x-fortran Size: 2475 bytes Desc: not available URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20120716/f9621f75/attachment.f>
[Wien] problem with joint program
The problem is in x_lapw in the section joint: the definition of unit 23 and 24 should have an "UNKNOWN" instead of "OLD" 23,'${scratch}$file.symmat1$updn' , 'UNKNOWN','FORMATTED', 0 24,'${scratch}$file.symmat2$updn' , 'UNKNOWN','FORMATTED', 0 The new version will have fixed this. Am 02.07.2012 22:28, schrieb Gavin Abo: > I think there is possibly a bug in SRC_joint that tries to open > "Fe.symmat1up", which seems to only be created by optic if xcmd = 1. > Probably, the code has to be modified to > create a blank file in SRC_optic or a condition to prevent the open may need > to be added for when xcmd = 0. > > Developers, can you please look into it? > > You could create a blank "Fe.symmat1up" and rerun x joint for the time being. > > On 7/2/2012 12:31 PM, Gavin Abo wrote: >> Try applying the fixed "opticpara_lapw " file at: >> >> http://zeus.theochem.tuwien.ac.at/pipermail/wien/2012-June/017036.html >> >> On 7/2/2012 11:52 AM, soumyajyoti haldar wrote: >>> Dear wien2k Developers, users and Prof. Blaha, >>> >>> I have one following questions / problems >>> >>> I am trying to do a test calculation of magneto-optic kerr effect with Fe. >>> I am using latest wien2k version compiled with intel composer-2011.3.174 >>> I am using following chain of commands witk k-point parallel option >>> >>> 1. runsp_lapw -p -i 100 -ec 0.01 -cc 0.001 -NI >>> 2. save_lapw >>> 3. initso_lapw >>> 4. runsp_lapw -p -so -dm -i 100 -ec 0.01 -cc 0.001 -NI >>> 5. Edit case.in2c file to change TOT to FERMI >>> 6. runsp_lapw -p -so -s lapw1 -e lcore >>> 7. x opticc -p -so -up >>> 8. x joint -p -up >>> >>> Everything runs perfectly upto command 7. but when I run x joint -p -up >>> then I got the following error >>> >>> 'JOINT' - can't open unit: 23 >>> 'JOINT' - filename: Fe.symmat1up >>> 'JOINT' - status: OLD form: FORMATTED >>> >>> After successful completion of 7th command I have only following file with >>> symmat >>> >>> >>> shaldar at pc-194-149:~/WIEN2k/Fe.error$ ls Fe.symmat* >>> Fe.symmat_11upFe.symmat_21upFe.symmat_31up Fe.symmat_41up >>> Fe.symmat_51upFe.symmat_61up Fe.symmatup >>> Fe.symmat_12upFe.symmat_22upFe.symmat_32up Fe.symmat_42up >>> Fe.symmat_52upFe.symmat_62up >>> >>> I am using following .machine file >>> >>> 1:localhost >>> 1:localhost >>> 1:localhost >>> 1:localhost >>> granularity:1 >>> extrafine:1 >>> >>> I am attaching the struct file I used to start the calculation from step 1. >>> If anyone can help where I am doing wrong then it will be helpful. >>> >>> thanks and regards >>> >>> >>> -- >>> Soumyajyoti Haldar, PhD Student >>> >>> Department of Physics and Astronomy, Materials Theory >>> ?ngstr?m Laboratory, Office ?13235 | Uppsala University >>> Box 516, SE-75120, Uppsala, SWEDEN >>> >>> Phone: (+46) 18 471 5860 >>> Mobile: (+46) 070 0399 394 >>> http://www.physics.uu.se/en/page/soumyajyoti-haldar >>> >>> >>> ___ >>> Wien mailing list >>> Wien at zeus.theochem.tuwien.ac.at >>> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien >> >> > > > > > ___ > Wien mailing list > Wien at zeus.theochem.tuwien.ac.at > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien > -- P.Blaha -- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 Email: blaha at theochem.tuwien.ac.atWWW: http://info.tuwien.ac.at/theochem/ --
[Wien] minimizing atomic positions and lattice constants simultaneously
Dear Prof. Marks & Wien2k users, I am very new user of wien2k (version 11.1) just started work about a month back and this is my first mail in this archive. I want to perform optimization of lattice constant and atomic positions simultaneously for an orthorhombic compound. I have gone through Optimization notes by L. D. Marks and as per I understand notes, I did following steps: (1) Calculate the total energy for 5 different volumes with fixed A:B:C ratio, and optimize the internal coordinates for each volume. (2) For each volumes, calculate the energy of five different c/a ratios and optimize the internal coordinates for each c/a ratio. (3) For each c/a ratios, calculate the total energy for five different volumes with fixed A:B:C ratio and optimize the internal coordinates for each volume. (4) Finally I have 5 volume directory and in each directories, I have 5 directories of c/a ratios with optimized internal positions (each with a set of 5 volumes ) now my question is: which file will give me optimized lattice constant and atomic positions both. Thanks in advance.
[Wien] minimizing atomic positions and lattice constants simultaneously
I think you have used a slightly long approach, and unless there is a typo error you have not done it quite right. Let's step back for a moment and think about the problem. For an orthorhombic cell (or did you mean tetragonal) a,b & c are all different. What you want to find is the minimum in the energy as a function of these three, E(a,b,c). Note, if tetragonal then it is just E(a,c) or E(a/c,V). Normally the largest change is with volume, so provided that the ratio's a/c and a/b are not very wrong you would optimize this first, then optimize the ratio's next. The volume would be option 1 in "x optimize". You could then do option 3 or 4 for each volume (vary c/a or b/a) although it is probably best to find the optimum volume first then use these. There are some tools for this in the web interface, although I almost always end up doing a simple fit with Excel. An alternative is to go directly to option 6 in "x optimize". If you have a tetragonal cell, you can take all the data you have and do a 2D fit to find the minimum energy. Again, there are some tools or you can use Excel. If it is orthorhombic then your step (3) was not write and you have not varied a/b yet and need to. Think about it a bit, it will become clearer. On Mon, Jul 16, 2012 at 6:40 AM, Pradeep Kumar wrote: > Dear Prof. Marks & Wien2k users, > > I am very new user of wien2k (version 11.1) just started work about a > month back and this is my first mail in this archive. > > I want to perform optimization of lattice constant and atomic > positions simultaneously for an orthorhombic compound. I have gone > through Optimization notes by L. D. Marks and as per I understand > notes, I did following steps: > > (1) Calculate the total energy for 5 different volumes with fixed > A:B:C ratio, and optimize the internal coordinates for each volume. > > (2) For each volumes, calculate the energy of five different c/a > ratios and optimize the internal coordinates for each c/a ratio. > > (3) For each c/a ratios, calculate the total energy for five different > volumes with fixed A:B:C ratio and optimize the internal coordinates > for each volume. > > (4) Finally I have 5 volume directory and in each directories, I have > 5 directories of c/a ratios with optimized internal positions (each > with a set of 5 volumes ) > > now my question is: which file will give me optimized lattice > constant and atomic positions both. > > Thanks in advance. > ___ > Wien mailing list > Wien at zeus.theochem.tuwien.ac.at > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien -- Professor Laurence Marks Department of Materials Science and Engineering Northwestern University www.numis.northwestern.edu 1-847-491-3996 "Research is to see what everybody else has seen, and to think what nobody else has thought" Albert Szent-Gyorgi
[Wien] problem with joint program
em.tuwien.**ac.at/mailman/listinfo/wien<http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien> >> >> > -- > > P.Blaha > --**--** > -- > Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna > Phone: +43-1-58801-165300 FAX: +43-1-58801-165982 > Email: blaha at theochem.tuwien.ac.atWWW: http://info.tuwien.ac.at/** > theochem/ <http://info.tuwien.ac.at/theochem/> > --**--** > -- > > > > > __**_ > Wien mailing list > Wien at zeus.theochem.tuwien.ac.**at > http://zeus.theochem.tuwien.**ac.at/mailman/listinfo/wien<http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien> > -- Soumyajyoti Haldar, PhD Student Department of Physics and Astronomy, Materials Theory ?ngstr?m Laboratory, Office ?13235 | Uppsala University Box 516, SE-75120, Uppsala, SWEDEN Phone: (+46) 18 471 5860 Mobile: (+46) 070 0399 394 http://www.physics.uu.se/en/page/soumyajyoti-haldar -- next part -- An HTML attachment was scrubbed... URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20120716/33a34a9b/attachment.htm>