Re: [Wien] Discrepancy in the simulation of the paramagnetic state
In the paramagnetic state, as Prof. Blaha says, the atoms still have magnetic moments but they are randomly oriented. This arises when the thermal energy is sufficient to overcome the spin-spin coupling. I would expect a calculation on Gd at 0K to give you a ferromagnetic state with very small spin-spin coupling. You can check the coupling by a run with one spin reversed. I am not convinced you can model a paramagnetic state with a DFT calculation and zero moments is not a good model. Your second example reads as though it is reporting experimental results on the magnetisation and does not seem to provide a model for calculations. I would also agree with Prof. Blaha about the factors influencing efg. Interatomic distance is very important in calculating this. Elaine A. Moore The Open University UK From: Wien on behalf of Abderrahmane Reggad Sent: 26 November 2016 21:30 To: wien@zeus.theochem.tuwien.ac.at Subject: Re: [Wien] Discrepancy in the simulation of the paramagnetic state Thank you Prof Blaha for your quick answer. The Ni atom is 3d transition metal . But my question is about the simulation of the paramagnetic state. There are many people that considere that the paramagnetic state is the non-spin polarierd one and the magnetic moment is zero, but you say no and the magnetic moments exist in arbitrary directions and my quoting is about that. I have given 2 examples for that discrepancy with your statement. Best regards -- Mr: A.Reggad Laboratoire de Génie Physique Université Ibn Khaldoun - Tiaret Algerie ___ 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] Discrepancy in the simulation of the paramagnetic state
How do you distinguish a diamagnetic, a paramagnetic, a ferromagnetic, and an antiferromagnetic state. Think ! This will answer your question, hopefully. 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 and Max Planck Institute for Chemical Physics of Solids 01187 Dresden Von: Wien [wien-boun...@zeus.theochem.tuwien.ac.at] im Auftrag von Abderrahmane Reggad [jazai...@gmail.com] Gesendet: Samstag, 26. November 2016 22:30 An: wien@zeus.theochem.tuwien.ac.at Betreff: Re: [Wien] Discrepancy in the simulation of the paramagnetic state Thank you Prof Blaha for your quick answer. The Ni atom is 3d transition metal . But my question is about the simulation of the paramagnetic state. There are many people that considere that the paramagnetic state is the non-spin polarierd one and the magnetic moment is zero, but you say no and the magnetic moments exist in arbitrary directions and my quoting is about that. I have given 2 examples for that discrepancy with your statement. Best regards -- Mr: A.Reggad Laboratoire de Génie Physique Université Ibn Khaldoun - Tiaret Algerie ___ 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] Discrepancy in the simulation of the paramagnetic state
Just to add one more point to this funny discussion, the term "paramagnetic" is sometimes used in the DFT litterature in an improper way. It could clearly lead to misunderstanding for researchers who do not know so much on how magnetic properties could evolve with temperature and applied magnetic field. When you see in a paper "paramagnetic state" simulated using DFT ... it is NOT paramagnetic at all, it is simply a trick which must be considered with care as previously mentionned by Peter, Eliane and Martin. If you want to simulate a paramagnetic state you need to include the temperature effects, i.e. you should consider the spin dynamics and the competition between magnetic exchange interactions and thermal fluctuations. This could be done, at least, using Monte-Carlo calculations based on an effective hamiltonian constructed on top of DFT parameters (including magnetic exchange and anisotropy at least). Best Regards Xavier Le 27/11/2016 à 10:01, Fecher, Gerhard a écrit : How do you distinguish a diamagnetic, a paramagnetic, a ferromagnetic, and an antiferromagnetic state. Think ! This will answer your question, hopefully. 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 and Max Planck Institute for Chemical Physics of Solids 01187 Dresden Von: Wien [wien-boun...@zeus.theochem.tuwien.ac.at] im Auftrag von Abderrahmane Reggad [jazai...@gmail.com] Gesendet: Samstag, 26. November 2016 22:30 An: wien@zeus.theochem.tuwien.ac.at Betreff: Re: [Wien] Discrepancy in the simulation of the paramagnetic state Thank you Prof Blaha for your quick answer. The Ni atom is 3d transition metal . But my question is about the simulation of the paramagnetic state. There are many people that considere that the paramagnetic state is the non-spin polarierd one and the magnetic moment is zero, but you say no and the magnetic moments exist in arbitrary directions and my quoting is about that. I have given 2 examples for that discrepancy with your statement. Best regards -- Mr: A.Reggad Laboratoire de Génie Physique Université Ibn Khaldoun - Tiaret Algerie ___ 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] Discrepancy in the simulation of the paramagnetic state
Thank you All for your contributions to enrich the subject . >From the beginning, I was convinced with the statement of prof Blaha, But when you find in literature some work where they simulate the paramagnetic state by the non-spin-polarized calculation this causes a troube. On this base, I needed a confirmation to this statement and it comes from all your contributions and clearly from Prof Roquefelt contribution. Thank you all again -- Mr: A.Reggad Laboratoire de Génie Physique Université Ibn Khaldoun - Tiaret Algerie ___ 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] it possible to apply first DFT+U and then mBJ+U?
Dear experts I did a calculation for hexagonal AgAlO2 and found that if I do first PBE+U and then apply mBJ+ U, it give smart band gap value which is very close to experimental band gap. But I do not know whether we can apply this U twice or not. The DFT+U calculation underestimates and only mBJ slightly overestimate the experimental band gap for this system. I did the calculation for -ec 0.1 -cc 0.0002 -fc 2 (setrmt -r 5). Any comment will be helpful. Sincerely Bhamu ___ 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] it possible to apply first DFT+U and then mBJ+U?
Dear Bhamu In the present case, you are dealing with Ag+ ions and thus a d10 electronic configuration for silver. In such a case applying a Hubbard correction will mainly lead to correct the position of the Ag(4d) states which are all occupied and below the O(2p) band. It should not affect so much the band gap. Do you have the band gap values when doing PBE only? I would recommend to do: - PBE - PBE+mBJ - and if you want to see the impact of the proper description of the 4d band of silver which is too high in energy when doing PBE only, you can apply an Hubbard term You must also consider the impact of relativistic treatment. For silver, the spin-orbit coupling will lead to split the p1/2 and p3/2 states which could contribute to the conduction band. Best Regards Xavier Le 27/11/2016 à 16:19, Dr. K. C. Bhamu a écrit : Dear experts I did a calculation for hexagonal AgAlO2 and found that if I do first PBE+U and then apply mBJ+ U, it give smart band gap value which is very close to experimental band gap. But I do not know whether we can apply this U twice or not. The DFT+U calculation underestimates and only mBJ slightly overestimate the experimental band gap for this system. I did the calculation for -ec 0.1 -cc 0.0002 -fc 2 (setrmt -r 5). Any comment will be helpful. Sincerely Bhamu ___ 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] How to include the localized d orbitals in the atomic spheres?
Dear wien users The orbital potential in DFT+U and EECE for localized orbitals will be included only inside the atomic spheres . To include these localized orbitals, we need a value for energy cut off larger than -6 Ry (maybe -2 Ry ). Is it the only way to include the localized orbitals in the atomic spheres since we can't reduce the Rmt values much. Best regards -- Mr: A.Reggad Laboratoire de Génie Physique Université Ibn Khaldoun - Tiaret Algerie ___ 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] How to include the localized d orbitals in the atomic spheres?
Huh?! This is not right. --- Professor Laurence Marks "Research is to see what everybody else has seen, and to think what nobody else has thought", Albert Szent-Gyorgi http://www.numis.northwestern.edu Corrosion in 4D http://MURI4D.numis.northwestern.edu Partner of the CFW 100% gender equity project, www.cfw.org/100-percent Co-Editor, Acta Cryst A On Nov 27, 2016 16:12, "Abderrahmane Reggad" wrote: > Dear wien users > > The orbital potential in DFT+U and EECE for localized orbitals will be > included only inside the atomic spheres . > > To include these localized orbitals, we need a value for energy cut off > larger than -6 Ry (maybe -2 Ry ). > > Is it the only way to include the localized orbitals in the atomic spheres > since we can't reduce the Rmt values much. > > Best regards > > > > -- > Mr: A.Reggad > Laboratoire de Génie Physique > Université Ibn Khaldoun - Tiaret > Algerie > > > ___ 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] Discrepancy in the simulation of the paramagnetic state
I hope you agree that Pt is paramagnetic I did two calculations for Pt, one was spin polarized the other not. The results are identical, no resulting magnetic moment (indeed, I started with one in the spin polarized case), did I play a trick or did Wien2k play a trick ? but may be Wien2k can not be used to calculate the electronic structure of Pt, because it is paramagnetic (Pt, not Wien2k !). I hope you agree that Pt is paramagnetic even at Zero temperature. why do I need to include temperature effects to calculate the ground state of Pt (at 0 K, where else) ? ... and what should MtC calculations tell me about it ? Remark 1: Calculations may be "spin polarized" (LSDA) or not (LDA) or they may be even more sophisticated "non-colinear spin polarized" or they may be for "disordred local moments" or for "spin spirals", or ???, just to name some. Remark 2: Materials may be diamagnetic, paramagnetic (Langevin, Pauli, van Vleck), ferromagnetic (localised moments, itinerant), ferrimagnetic (collinear, non-collinear), etc.. Therefore, I repeat my question: How do you distinguish diamagnetic, paramagnetic, ferromagnetic, and ... states ? The answer is for you, not for me. I tried to calculate for Pt using Hohenberg Kohn DFT, but I could not find the functional, all I found was some approximation using wave functions. Don't worry I will not ask a question about it ;-) 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 and Max Planck Institute for Chemical Physics of Solids 01187 Dresden Von: Wien [wien-boun...@zeus.theochem.tuwien.ac.at] im Auftrag von Xavier Rocquefelte [xavier.rocquefe...@univ-rennes1.fr] Gesendet: Sonntag, 27. November 2016 12:46 An: wien@zeus.theochem.tuwien.ac.at Betreff: Re: [Wien] Discrepancy in the simulation of the paramagnetic state Just to add one more point to this funny discussion, the term "paramagnetic" is sometimes used in the DFT litterature in an improper way. It could clearly lead to misunderstanding for researchers who do not know so much on how magnetic properties could evolve with temperature and applied magnetic field. When you see in a paper "paramagnetic state" simulated using DFT ... it is NOT paramagnetic at all, it is simply a trick which must be considered with care as previously mentionned by Peter, Eliane and Martin. If you want to simulate a paramagnetic state you need to include the temperature effects, i.e. you should consider the spin dynamics and the competition between magnetic exchange interactions and thermal fluctuations. This could be done, at least, using Monte-Carlo calculations based on an effective hamiltonian constructed on top of DFT parameters (including magnetic exchange and anisotropy at least). Best Regards Xavier Le 27/11/2016 à 10:01, Fecher, Gerhard a écrit : > How do you distinguish a diamagnetic, a paramagnetic, a ferromagnetic, and an > antiferromagnetic state. > > Think ! > > This will answer your question, hopefully. > > 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 > and > Max Planck Institute for Chemical Physics of Solids > 01187 Dresden > > Von: Wien [wien-boun...@zeus.theochem.tuwien.ac.at] im Auftrag von > Abderrahmane Reggad [jazai...@gmail.com] > Gesendet: Samstag, 26. November 2016 22:30 > An: wien@zeus.theochem.tuwien.ac.at > Betreff: Re: [Wien] Discrepancy in the simulation of the paramagnetic state > > Thank you Prof Blaha for your quick answer. > > The Ni atom is 3d transition metal . But my question is about the simulation > of the paramagnetic state. There are many people that considere that the > paramagnetic state is the non-spin polarierd one and the magnetic moment is > zero, but you say no and the magnetic moments exist in arbitrary directions > and my quoting is about that. > > I have given 2 examples for that discrepancy with your statement. > > Best regards > -- > Mr: A.Reggad > Laboratoire de Génie Physique > Université Ibn Khaldoun - Tiaret > Algerie > > > ___ > 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 htt
Re: [Wien] How to include the localized d orbitals in the atomic spheres?
Either the language is wrong or your Question/Conclusion is wrong I suggest to read and understand -- besides the Wien2k manual -- also some basic textbooks on the subject, for example Richard Martin, Electronic structure, Cambridge Jürgen Kübler, Theory of itinerant electron magnetism, Oxford to avoid any misunderstandings. 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 and Max Planck Institute for Chemical Physics of Solids 01187 Dresden Von: Wien [wien-boun...@zeus.theochem.tuwien.ac.at] im Auftrag von Abderrahmane Reggad [jazai...@gmail.com] Gesendet: Sonntag, 27. November 2016 23:12 An: wien@zeus.theochem.tuwien.ac.at Betreff: [Wien] How to include the localized d orbitals in the atomic spheres? Dear wien users The orbital potential in DFT+U and EECE for localized orbitals will be included only inside the atomic spheres . To include these localized orbitals, we need a value for energy cut off larger than -6 Ry (maybe -2 Ry ). Is it the only way to include the localized orbitals in the atomic spheres since we can't reduce the Rmt values much. Best regards -- Mr: A.Reggad Laboratoire de Génie Physique Université Ibn Khaldoun - Tiaret Algerie ___ 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