Re: [Wien] crystal field splitting
Dear professor Vñictor Luaña: Thanks very much for your kindly reply. Your reply is really helpful and I will go on studying in this field. Thanks again. Sincerely Wangwei Lan From: wien-boun...@zeus.theochem.tuwien.ac.at wien-boun...@zeus.theochem.tuwien.ac.at on behalf of Víctor Luaña Cabal vic...@fluor.quimica.uniovi.es Sent: Sunday, August 23, 2015 15:37 To: A Mailing list for WIEN2k users Cc: Victor Luaña Subject: Re: [Wien] crystal field splitting On Sun, Aug 23, 2015 at 07:51:33PM +, Lan, Wangwei wrote: Dear Wien2k user: I am very new in WIEN2k. Now I am running case on our crystal system which contains a transition metal Cr. I am particularly interested in the d orbital splitting, the energy levels of 5 d orbitals. Does anyone know how to calculate the orbital splitting using WIEN2k? Wangwei, The answer is not simple and there can be more than one opinion living around. Let me express mu 0.02 euros. Crystal field splitting parameters (delta-D, i.e. t2g-eg splitting, Racah parameters, etc) is by fitting a model to the theoretical or experimental true calculations of total energy diferences between correlated electronic states. In other terms, there are no such a thing as orbital splitting as a well defined element. The orbital approach is a interpretative description, not a physical definition. There are decades that I not contribute to this old subject and I reccomend you to follow the more recent papers by Profs. Luis Seijo and Zoila Barandiarán, from the UAM (Universidad Aotónoma de Madrid). You will find in their work a good description of old and modern treatments, laike MOLCAS calculations, relativity contributions, and the huge importance of large correlation treatments. Both contribute to the development of MOLCAS. http://www.uam.es/personal_pdi/ciencias/lseijo/ http://www.uam.es/personal_pdi/ciencias/yara/ Notice that the field emerged from dealing with impurities within crystals, so most of the evolution that I learned was releted to the moleculartreatment of embedded impurities neighborhoods. On a solid state perspective, and your mention of wannier functions lets me thing you may prefer that, notice that d-d, d-s and d-p transitions correspond to heavily correlated problems, and the wave funcion perspective has a much longer tradition than TD-DFT ones, but let me just say that I know less abiout them. The conferences by Stefano Baroni on the calculation of the color of natural dies are simple awesome. http://stefano.baroni.me/presentations.html Best regards and good luck if you come new to this field, Dr. Vñictor Luaña -- . .In science a person can be convinced by a good argument. / `' \ That is almost impossible in politics or religion /(o)(o)\ (Adapted from Carl Sagan) /`. \/ .'\ Lo mediocre es peor que lo bueno, pero también es peor / '`'` \ que lo malo, porque la mediocridad no es un grado, es una | \'`'`/ | actitud -- Jorge Wasenberg, 2015 | |'`'`| | (Mediocre is worse than good, but it is also worse than \/`'`'`'\/ bad, because mediocrity is not a grade, it is an attitude) ===(((==)))==+= ! Dr.Víctor Luaña, in silico chemist prof. ! I hate the bureaucracy ! Departamento de Química Física y Analítica ! imposed by companies to ! Universidad de Oviedo, 33006-Oviedo, Spain ! which I owe nothing: ! e-mail: vic...@fluor.quimica.uniovi.es ! amazon, ResearchGATE and ! phone: +34-985-103491 fax: +34-985-103125 ! the like. ++ GroupPage : http://azufre.quimica.uniovi.es/ (being reworked) ___ 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] crystal field splitting
On Sun, Aug 23, 2015 at 07:51:33PM +, Lan, Wangwei wrote: Dear Wien2k user: I am very new in WIEN2k. Now I am running case on our crystal system which contains a transition metal Cr. I am particularly interested in the d orbital splitting, the energy levels of 5 d orbitals. Does anyone know how to calculate the orbital splitting using WIEN2k? Wangwei, The answer is not simple and there can be more than one opinion living around. Let me express mu 0.02 euros. Crystal field splitting parameters (delta-D, i.e. t2g-eg splitting, Racah parameters, etc) is by fitting a model to the theoretical or experimental true calculations of total energy diferences between correlated electronic states. In other terms, there are no such a thing as orbital splitting as a well defined element. The orbital approach is a interpretative description, not a physical definition. There are decades that I not contribute to this old subject and I reccomend you to follow the more recent papers by Profs. Luis Seijo and Zoila Barandiarán, from the UAM (Universidad Aotónoma de Madrid). You will find in their work a good description of old and modern treatments, laike MOLCAS calculations, relativity contributions, and the huge importance of large correlation treatments. Both contribute to the development of MOLCAS. http://www.uam.es/personal_pdi/ciencias/lseijo/ http://www.uam.es/personal_pdi/ciencias/yara/ Notice that the field emerged from dealing with impurities within crystals, so most of the evolution that I learned was releted to the moleculartreatment of embedded impurities neighborhoods. On a solid state perspective, and your mention of wannier functions lets me thing you may prefer that, notice that d-d, d-s and d-p transitions correspond to heavily correlated problems, and the wave funcion perspective has a much longer tradition than TD-DFT ones, but let me just say that I know less abiout them. The conferences by Stefano Baroni on the calculation of the color of natural dies are simple awesome. http://stefano.baroni.me/presentations.html Best regards and good luck if you come new to this field, Dr. Vñictor Luaña -- . .In science a person can be convinced by a good argument. / `' \ That is almost impossible in politics or religion /(o)(o)\ (Adapted from Carl Sagan) /`. \/ .'\ Lo mediocre es peor que lo bueno, pero también es peor / '`'` \ que lo malo, porque la mediocridad no es un grado, es una | \'`'`/ | actitud -- Jorge Wasenberg, 2015 | |'`'`| | (Mediocre is worse than good, but it is also worse than \/`'`'`'\/ bad, because mediocrity is not a grade, it is an attitude) ===(((==)))==+= ! Dr.Víctor Luaña, in silico chemist prof. ! I hate the bureaucracy ! Departamento de Química Física y Analítica ! imposed by companies to ! Universidad de Oviedo, 33006-Oviedo, Spain ! which I owe nothing: ! e-mail: vic...@fluor.quimica.uniovi.es ! amazon, ResearchGATE and ! phone: +34-985-103491 fax: +34-985-103125 ! the like. ++ GroupPage : http://azufre.quimica.uniovi.es/ (being reworked) ___ 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] Crystal field splitting
Dear Salman, unfortunately I have neither means (no Wien2k on my notebook) nor time right now to quickly provide an answer to your problems. Anyhow, directing you to literature you can cite is probably better than an elaborate email lecture on crystal field splittings (not being really an expert I am not the ideal person to give such a lecture anyway). To me the best way to proceed seems to be be: - get your hands on some textbook on magnetism with a chapter on crystal field effects. Kei Yosida: Theory of Magnetism, Springer Series in Solid State Science vol 122 might be one choice. Personally, when I ran into crystal field effects a rather long time ago, I liked the article of M. T. Hutchings: Point charge ... in F. Seitz, D. Turnbull, Solid State Physics, vol. 16, p. 227, Academic Press 1964. - read (understand) that chapter. You should know at this stage which parameters appear in the crystal field Hamiltonian if you know L and the point symmetry. I did not use Pavel Novaks new package for Wien2k up to now but I expect that you can understand its I/O on that basis. And you should be aware of the limitations of the concept, especially in a 3d-metal! - Find the configuration of B nearest neighbors for the two non-equivalent Ni sites in your structure. The idea is that charges farther out are pretty much shielded. Simply look at the structure using Xcrysden or something similar to identify this configuration. In Wien2k, outputnn gives you the number and position of these B atoms. My guess (a guess, not more!) is, that one Ni site has a (distorted) octahedral configuration, the other a (also distorted) tetrahedral one. CF splitting usually is considered in steps of decreasing importance of the contribution in the Hamiltonian: first approximate the situation by a cubic crystal field, then take into account, say, tetragonal distortions of the ideal octahedron, and so on, lowering symmetry in each step. I hope this helps, Martin --- Dr. Martin Pieper Karl-Franzens University Institute of Physics Universitätsplatz 5 A-8010 Graz Austria Tel.: +43-(0)316-380-8564 Am 03.11.2014 13:41, schrieb Salman Zarrini: +++ Dear Martin and Delamora, Many thanks for your answer, actually, controversial state for me here is 3d orbitals of Ni elements crystalline together with boron in a orthorhombic structure, Pnma space group. I can see different kind of point group in case.outputsgroup(1,1,C1 for sort one, m,m,Cs for atom sort 2 and m,m,Cs for atom sort 3 and a mmm,2/m,2/m 2/m,D2h in the end for the whole structure)but I can not make a link between them and potential crystal filed splitting for this structure, for convenience the struct file has been enclosed, I would be thankful if you guided me to find the proper crystal filed. Cheers, Salman +++ ___ 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] Crystal field splitting
Dear Salman, to be a little bit more precise, crystal field splitting is a local concept: The Coulomb interaction of all electrons in a given shell characterized by its angular momentum with the surrounding charge distribution is represented by a minimal set of angular momentum operators. To make sense this should to be a shell of reasonably well localized electrons (usually a 4f-shell). If you have a metal the bandwidth of that particular band should be small, the conduction electrons should be contributed by other shells. It also means that it is NOT the overall crystal symmetry you have to consider, but the point symmetry group of the crystalografic site occupied by the (Rare Earth?) element you are interested in. When your structure has sites with, say, octahedral and tetrahedral symmetry the crystal field Hamiltonian (and its eigenvalues, the splitting) will reflect these symmetries. The point group symmetries are tabulated, e.g. for the Wyckoff positions at the Bilbao server (http://www.cryst.ehu.es/) Best regards, Martin --- Dr. Martin Pieper Karl-Franzens University Institute of Physics Universitätsplatz 5 A-8010 Graz Austria Tel.: +43-(0)316-380-8564 Am 03.11.2014 03:56, schrieb delamora: The crystal field splitting depends on the crystal symmetry!!, but for a compound with metallic characteristics the bandwidth will be larger that the field splitting. De: wien-boun...@zeus.theochem.tuwien.ac.at wien-boun...@zeus.theochem.tuwien.ac.at en nombre de Salman Zarrini salman.zarr...@tu-darmstadt.de Enviado: domingo, 02 de noviembre de 2014 04:57 p.m. Para: wien@zeus.theochem.tuwien.ac.at Asunto: [Wien] Crystal field splitting Dear Wien2k users, I was wondering that how can I find out which kinds of crystal field splitting (Octahedral, Tetrahedral, Pentagonal bipyramidal,...) have been applied on my bulk metallic structure? Best regards, Salman ___ 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 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] Crystal field splitting
+++ Dear Martin and Delamora, Many thanks for your answer, actually, controversial state for me here is 3d orbitals of Ni elements crystalline together with boron in a orthorhombic structure, Pnma space group. I can see different kind of point group in case.outputsgroup(1,1,C1 for sort one, m,m,Cs for atom sort 2 and m,m,Cs for atom sort 3 and a mmm,2/m,2/m 2/m,D2h in the end for the whole structure)but I can not make a link between them and potential crystal filed splitting for this structure, for convenience the struct file has been enclosed, I would be thankful if you guided me to find the proper crystal filed. Cheers, Salman +++ ni3b P362_Pnma RELA 9.85 12.494418 8.292604 90.00 90.00 90.00 ATOM -1: X=0.18024000 Y=0.06237541 Z=0.15479748 MULT= 8 ISPLIT= 8 -1: X=0.81976000 Y=0.93762459 Z=0.84520252 -1: X=0.68024000 Y=0.06237541 Z=0.34520252 -1: X=0.31976000 Y=0.93762459 Z=0.65479748 -1: X=0.31976000 Y=0.56237541 Z=0.65479748 -1: X=0.68024000 Y=0.43762459 Z=0.34520252 -1: X=0.81976000 Y=0.56237541 Z=0.84520252 -1: X=0.18024000 Y=0.43762459 Z=0.15479748 Ni NPT= 781 R0=0.5000 RMT=2.1100 Z: 28.0 LOCAL ROT MATRIX:1.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 1.000 ATOM -2: X=0.02795073 Y=0.2500 Z=0.63114648 MULT= 4 ISPLIT= 8 -2: X=0.97204927 Y=0.7500 Z=0.36885352 -2: X=0.52795073 Y=0.2500 Z=0.86885352 -2: X=0.47204927 Y=0.7500 Z=0.13114648 Ni NPT= 781 R0=0.5000 RMT=2.1100 Z: 28.0 LOCAL ROT MATRIX:0.000 1.000 0.000 0.000 0.000 1.000 1.000 0.000 0.000 ATOM -3: X=0.38206182 Y=0.2500 Z=0.43792072 MULT= 4 ISPLIT= 8 -3: X=0.61793818 Y=0.7500 Z=0.56207928 -3: X=0.88206182 Y=0.2500 Z=0.06207928 -3: X=0.11793818 Y=0.7500 Z=0.93792072 B NPT= 781 R0=0.0001 RMT=1.5600 Z: 5.0 LOCAL ROT MATRIX:0.000 1.000 0.000 0.000 0.000 1.000 1.000 0.000 0.000 8 NUMBER OF SYMMETRY OPERATIONS -1 0 0 0. 0-1 0 0. 0 0-1 0. 1 1 0 0 0. 0 1 0 0. 0 0 1 0. 2 -1 0 0 0.5000 0-1 0 0. 0 0 1 0.5000 3 -1 0 0 0. 0 1 0 0.5000 0 0-1 0. 4 -1 0 0 0.5000 0 1 0 0.5000 0 0 1 0.5000 5 1 0 0 0.5000 0-1 0 0.5000 0 0-1 0.5000 6 1 0 0 0. 0-1 0 0.5000 0 0 1 0. 7 1 0 0 0.5000 0 1 0 0. 0 0-1 0.5000 8___ 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] Crystal field splitting
The crystal field splitting depends on the crystal symmetry!!, but for a compound with metallic characteristics the bandwidth will be larger that the field splitting. De: wien-boun...@zeus.theochem.tuwien.ac.at wien-boun...@zeus.theochem.tuwien.ac.at en nombre de Salman Zarrini salman.zarr...@tu-darmstadt.de Enviado: domingo, 02 de noviembre de 2014 04:57 p.m. Para: wien@zeus.theochem.tuwien.ac.at Asunto: [Wien] Crystal field splitting Dear Wien2k users, I was wondering that how can I find out which kinds of crystal field splitting (Octahedral, Tetrahedral, Pentagonal bipyramidal,...) have been applied on my bulk metallic structure? Best regards, Salman ___ 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
