Re: [Wien] Calculation about the effect of external magnetic field
How strong was the field ? If you have a magnetic material saturated (say Fe at about 2.2. mu_B, I guess that's what you have already without magnetic field), what changes do you expect when you apply a magnetic field on top of the saturation ? Application of a magnetic field in the calculation may stabilyse a otherwise metastable magnetic solution. Ciao Gerhard DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy: I think the problem, to be quite honest with you, is that you have never actually known what the question is. Dr. Gerhard H. Fecher Institut of Inorganic and Analytical Chemistry Johannes Gutenberg - University 55099 Mainz Von: wien-boun...@zeus.theochem.tuwien.ac.at [wien-boun...@zeus.theochem.tuwien.ac.at]quot; im Auftrag von quot;李艳丽 [liyanli...@163.com] Gesendet: Dienstag, 2. September 2014 06:19 An: wien@zeus.theochem.tuwien.ac.at Betreff: [Wien] Calculation about the effect of external magnetic field Dear all, I notice that a external magnetic field could be applied in wien2k by orb. And I used the order ' runsp_lapw -ec 0.0001 -orb -p ' to calculate the effect of external magnetic field on the electronic structures of Fe3O4, and there are no change happened. I also tried many tests on other materials, and the results are also the same with that without the external magnetic field. So it means the external magnetic field has no effect on the properties of the materials, which is not consistent with the experimental results. Therefore I want to know whether the function of adding external magnetic field worked ? Best Regards, Yanli Wuhan University of Science and Technology, Wuhan, P.R.China 430070 ___ 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] mBJ usability and relevance for semiconductor/metal heterostructures?
Dear Wien2k users, I would like to ask you to share your opinion about relevance of mBJ potential used in study of semiconductor/metal heterostructures. The question would be -- How should be fixed value of the c parameter? In case of a supercell (.../SC/M/...) approach (no vacuum) should one consider a bulk semiconductor value for the c? What consider for the c in case of a slab ( .../SC/M/vacuum/...)? Best regards, Martin Gmitra Uni Regensburg ___ 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] mBJ usability and relevance for semiconductor/metal heterostructures?
Hi, Most likely the semiconductor and metal will require different values of c. Furthermore, mBJ is maybe not the best choice for metals, and for Fe, Co, Ni a value of c smaller than 1 is more appropriate for the magnetic moment [Koller et al., PRB 83, 195134 (2011)]. It's not easy to say in advance which c is the most appropriate for such heterostructures. Maybe tunning c until an experimental value is reproduced. For sure the vacuum should not be used to fix x. F. Tran On Tue, 2 Sep 2014, Martin Gmitra wrote: Dear Wien2k users, I would like to ask you to share your opinion about relevance of mBJ potential used in study of semiconductor/metal heterostructures. The question would be -- How should be fixed value of the c parameter? In case of a supercell (.../SC/M/...) approach (no vacuum) should one consider a bulk semiconductor value for the c? What consider for the c in case of a slab ( .../SC/M/vacuum/...)? Best regards, Martin Gmitra Uni Regensburg ___ 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
[Wien] Hard charge convergence
Dear Wien2k community, I would like some general hints for a system with a difficult charge convergence. In my case, I got the energy convergence (-ec 0.0001), but not the charge one (-cc 0.0001). Would it be acceptable to increase the charge convergence criterion to -cc 0.0005 ? I am getting charge changes bellow this value. All the best, Luis ___ 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] Hard charge convergence
Hi, It depends on your needs. Just use the command grep to see if the quantity you are interested in particular (e.g., magnetic moment or band gap) seems to have reached a degree of convergence which satisfies you. F. Tran On Tue, 2 Sep 2014, Luis Ogando wrote: Dear Wien2k community, I would like some general hints for a system with a difficult charge convergence. In my case, I got the energy convergence (-ec 0.0001), but not the charge one (-cc 0.0001). Would it be acceptable to increase the charge convergence criterion to -cc 0.0005 ? I am getting charge changes bellow this value. All the best, Luis ___ 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] Hard charge convergence
Dear Professor Tran, Thank you for your response. Actually, I am doing structure optimization, so energy is the most important parameter (and forces due to free parameters). Perhaps, I am being too strict when asking for charge convergence during structure optimization. What is your opinion ? Thank you again. All the best, Luis 2014-09-02 16:59 GMT-03:00 t...@theochem.tuwien.ac.at: Hi, It depends on your needs. Just use the command grep to see if the quantity you are interested in particular (e.g., magnetic moment or band gap) seems to have reached a degree of convergence which satisfies you. F. Tran On Tue, 2 Sep 2014, Luis Ogando wrote: Dear Wien2k community, I would like some general hints for a system with a difficult charge convergence. In my case, I got the energy convergence (-ec 0.0001), but not the charge one (-cc 0.0001). Would it be acceptable to increase the charge convergence criterion to -cc 0.0005 ? I am getting charge changes bellow this value. All the best, Luis ___ 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] Hard charge convergence
What is important for geometry optimization is to require also force convergence (-fc) with a value like 0.5 or 1 (see user's guide). On Tue, 2 Sep 2014, Luis Ogando wrote: Dear Professor Tran, Thank you for your response. Actually, I am doing structure optimization, so energy is the most important parameter (and forces due to free parameters). Perhaps, I am being too strict when asking for charge convergence during structure optimization. What is your opinion ? Thank you again. All the best, Luis 2014-09-02 16:59 GMT-03:00 t...@theochem.tuwien.ac.at: Hi, It depends on your needs. Just use the command grep to see if the quantity you are interested in particular (e.g., magnetic moment or band gap) seems to have reached a degree of convergence which satisfies you. F. Tran On Tue, 2 Sep 2014, Luis Ogando wrote: Dear Wien2k community, I would like some general hints for a system with a difficult charge convergence. In my case, I got the energy convergence (-ec 0.0001), but not the charge one (-cc 0.0001). Would it be acceptable to increase the charge convergence criterion to -cc 0.0005 ? I am getting charge changes bellow this value. All the best, Luis ___ 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
