Re: [Wien] temperature dependent DFT (band, ...) calculations
Regarding the question of temperature effects, let me add some remarks about electronic temperature. Under diverse circumstances (e.g. laser heating) it is possible for the electrons and phonons to have very different temperatures for experimentally meaningfully long times. Of course it also is possible for the two populations to be at equilibrium at a temperature that is high with respect to some important criterion. In either case, finite-temperature or free-energy DFT can be important for calculation. Free energy DFT has been known since Mermin's paper in 1965. Superficially, the computation looks like a ground-state Kohn-Sham equation with non-integer Fermi-Dirac approximations. Often that superficial resemblance has led people to implement calculations by taking an ordinary ground state XC functional, e.g. PBE, and stuffing in a finite-T density. For comparatively low electronic temperatures, up to several thousand Kelvin (i.e. about 0.75 eV) perhaps, that is reasonably OK for equations of state, conductivity, etc. Above that it is not OK (despite some expert opinion to the contrary) and one should use exchange-correlation free energy density functional approximations. Our group has worked very intensely on this problem. Details are in "Status of free-energy representations for the homogeneous electron gas" V.V. Karasiev, S.B. Trickey, and J.W. Dufty, Phys. Rev. B 99, 195134 (2019) "Nonempirical Semi-local Free-Energy Density Functional for Matter Under Extreme Conditions: V.V. Karasiev, J.W. Dufty, and S.B. Trickey, Phys. Rev. Lett. 120, 076401 (2018) "Importance of Finite-temperature Exchange-correlation for Warm Dense Matter Calculations" V.V. Karasiev, L. Calder\'in, and S.B. Trickey, Phys. Rev. E 93, 063207 (2016) "Accurate Homogeneous Electron Gas Exchange-correlation Free Energy for Local Spin-density Calculations" V.V. Karasiev, T. Sjostrom, J. Dufty, and S.B. Trickey, Phys. Rev. Lett. 112, 076403 (2014) "Innovations in Finite-Temperature Density Functionals" V.V. Karasiev, T. Sjostrom, D.Chakraborty, J.W. Dufty, F.E. Harris, K. Runge, and S.B. Trickey, in "Frontiers and Challenges in Warm Dense Matter", F. Graziani et al. eds., (Springer, Heidelberg, 2014) 61-85. References to the other literature are in our papers. All of them are downloadable from www.qtp.ufl.edu/ofdft Also, some time ago Andreas G\"orling and colleagues at Erlangen worked out finite-T exact exchange and gave examples M. Greiner, P. Carrier, and A. G\"orling Phys. Rev. B 81, 155119 [12 pp] (2010) and more recently Andreas and his student Trushin have applied it to topological phase transitions Egor Trushin and Andreas G\"orling Phys. Rev. Lett. 120, 146401 [5 pp] (2018) Perhaps this will be helpful. Peace, Sam On 4/18/2020 11:42 AM, Peter Blaha wrote: [External Email] If you are lucky, yes, but in general, the answer is NO !!! The lattice parameter is only a "mean value", and is a "prerequisite" for a finit temp calculation. But think about: what means "Termperature" ? It vibrations, which are excited more or less with T. The atoms move around heavily and this can be even anisotropic. And one measures basically an average of a certain quantity while the atoms are vibrating around. Calculating phonons gives you entropy and free energies; Doing properties with temperature dependent average displacements gives you properties at finite T. One example: Physical Review B, 98 (2018), S. 235205. Am 18.04.2020 um 15:33 schrieb Dr. K. C. Bhamu: Dear Experts, Could you please confirm that if I have temperature dependent lattice parameters, from DFT calculation, then whatever properties like band, phonon, elastic, ... , I compute will be considered as temperature dependent ? Yes, ionic positions should be relaxed what I know. My own answer would be yes for this query but I need a confirmation. It would be a help from computational resources point of view. I do not want to test the calculation and see the the difference as system is more computational time demanding. Thank you very much. Regards Bhamu ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at https://urldefense.proofpoint.com/v2/url?u=http-3A__zeus.theochem.tuwien.ac.at_mailman_listinfo_wien=DwIGaQ=sJ6xIWYx-zLMB3EPkvcnVg=3u4OCHnAtdypMfYN_K57COVk2XByDoKwnLuc_zRENzE=dAw8pTU_XxT09rXzC5WjivkrsCXLc1i0e3DPWpsJZyU=OXDD9F14PPphtuS-fwtV0KHjOUCxxklnWsyi72Z0-BE= SEARCH the MAILING-LIST at: https://urldefense.proofpoint.com/v2/url?u=http-3A__www.mail-2Darchive.com_wien-40zeus.theochem.tuwien.ac.at_index.html=DwIGaQ=sJ6xIWYx-zLMB3EPkvcnVg=3u4OCHnAtdypMfYN_K57COVk2XByDoKwnLuc_zRENzE=dAw8pTU_XxT09rXzC5WjivkrsCXLc1i0e3DPWpsJZyU=TCXpiFspGc8XyLY0qnTjPaEYsG8OmJ2g0uEst0HEc8E= -- -- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-165300 FAX:
Re: [Wien] gfortran compilation and run problems for 19.1
See below On 6/25/19 5:47 AM, Peter Blaha wrote: Hi, I can confirm the fix for inputpars.F. Of course, according to fortran standards a logical if should have an .eqv. operator (although I never "understood" what that should be good for ...). Keeps computer scientists occupied introducing needless and annoying distinctions. peace, Sam -- Samuel B. Trickey QTP, Depts. of Physics and Chemistry 2324 Physics Building Box 118435 Univ. of Florida Gainesville, FL 32611-8435 Vox: 352-392-6978 (direct) Vox: 352-392-1597 (receptionist) Fax: 352-392-8722 http://www.qtp.ufl.edu/ofdft http://users.clas.ufl.edu/trickey ___ 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] core-hole calculation in a molecule
Good morning - Maybe I can give a little help. I never tried a core-electron binding energy. Long ago, with the old Univ. Florida APW (NOT LAPW!) code, Asok Ray, Joe Worth, and I did try the Slater transition state for optical transitions in rare gas crystals. We implemented it in a periodic way, with half an electron moved above the Fermi level in each unit cell. That, in essence is a Slater transition state treatment of an exciton. It was all done in the context of X-alpha but that is not a relevant restriction. The citation is S.B. Trickey, A.K. Ray, and J.P. Worth, Phys. Stat. Solidi (b) 106, 613 - 620 (1981). Peace, Sam On 6/19/19 8:57 AM, Pavel Ondračka wrote: Dear Wien2k mailing list, I'm trying to calculate core electron binding energies using the Slaters transition state approach (half electron removed from the core compensated by the background charge) in an organic molecule. As part of the usual convergence checking I did four calculations with different amount of vacuum, with 5Å, 10Å, 15Å and 20Å in all directions in order to get some trend and try to extrapolate the final values. This is the approach similar to what I use for insulators (increasing supercell size), to estimate the supercell size error due to the Coulomb interaction between the periodic images of the charged atom. However to my first surprise there is no change in the binding energies (~0.01 eV) observed. Thinking about it more it makes sense though, as there is no screening in the vacuum, so there probably is no reduction of the interaction (like in the simple electrostatic example where the electric field intensity next to the infinite charged plane doesn't depend on the distance to it). I'm looking for an advice whether someone already tried something like this and if this kind of calculation (i.e., corehole for molecule, single atom, or even a 2D material) actually makes a sense from the physical point of view and also within the lapw framework... For now I'm comparing the relative shifts of the core electron binding energies of different carbon atoms within the molecule, and the results looks quite in agreement with the literature. However I'm not sure how much I can trust the results and if I can actually compare the values also with bulk materials. Any advice would be appreciated Best regards Pavel ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at https://urldefense.proofpoint.com/v2/url?u=http-3A__zeus.theochem.tuwien.ac.at_mailman_listinfo_wien=DwIGaQ=sJ6xIWYx-zLMB3EPkvcnVg=3u4OCHnAtdypMfYN_K57COVk2XByDoKwnLuc_zRENzE=7u96YzPTDOXtZFG5IaP1ziksOIzobRyosdGDybvjjlI=L43AgO44OfheESgHkJjs5NtZN6Z0mVHpeWgVs4MGJk8= SEARCH the MAILING-LIST at: https://urldefense.proofpoint.com/v2/url?u=http-3A__www.mail-2Darchive.com_wien-40zeus.theochem.tuwien.ac.at_index.html=DwIGaQ=sJ6xIWYx-zLMB3EPkvcnVg=3u4OCHnAtdypMfYN_K57COVk2XByDoKwnLuc_zRENzE=7u96YzPTDOXtZFG5IaP1ziksOIzobRyosdGDybvjjlI=VyGp6-1XiVhkxbS6x29WCNp6m2WYIBytMt08uqoBZfM= -- Samuel B. Trickey QTP, Depts. of Physics and Chemistry 2324 Physics Building Box 118435 Univ. of Florida Gainesville, FL 32611-8435 Vox: 352-392-6978 (direct) Vox: 352-392-1597 (receptionist) Fax: 352-392-8722 http://www.qtp.ufl.edu/ofdft http://users.clas.ufl.edu/trickey ___ 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] Augmented Plane Wave
Rarely do I contribute to this list, though I benefit from reading it. I must respectfully contradict Martin. Professor Slater clearly intended that the augmentation be of the plane wave. The history, at least as I know it, is this. Professor Slater did not use the word "augment" or "augmented" in his 1937 paper that usually is cited as the original APW paper [Rev. 51, 846 (1937)]. So far as I am aware, the first time he used the phrase "augmented plane wave" is in Phys. Rev. 92, 603 (1953). The phrase appears in the title but, more important for discerning his intent is the discussion beginning on the bottom right of p. 603 and continuing on 604. He introduces Herring's orthogonalized plane waves and summarizes their applications and then says (lines 7-9, LH column, p. 604) "Relatively few such orthogonalized or augmented plane waves suffice to give a rather good approximate wave function." Noting the problem of non-existent orthogonalization of a 2p-like state to a deeper core state found by Frank Herman, Prof. Slater goes on to say "Herman has suggested that in such a case we could augment the plane wave ...". He opens the next paragraph with "The present method may be regarded as a straight-forward procedure for augmenting a plane wave by adding to it a contribution near each nucleus ...". It may be useful to add that I was part of Prof. Slater's group within QTP for the last 7-1/2 years of his life and one year was assigned (even though I was an Asst. Prof. not a post-doc!) to be his teaching assistant in his "Quantum Theory of Matter" course. Those experiences were consistent with the sentences just quoted. Peace, Sam On 3/22/19 7:04 AM, pieper wrote: Dear Pablo, I suspect your problem occurs because you left out the word which "Augmented" refers too: It is an "Augmented Plane Wave Method", that is, the Method is augmented (including additional basis functions), not the plane waves (in amplitude or intensity). Best regards, Martin Pieper --- Dr. Martin Pieper Karl-Franzens University Institute of Physics Universitätsplatz 5 A-8010 Graz Austria Tel.: +43-(0)316-380-8564 Am 2019-03-22 02:49, schrieb delamora: Dear Wien users, I have a question about the name of "Augmented Plane Wave" I had the idea that when the wave enters the Muffin Tin sphere the amplitude of the wave increased. Trying to see this I found that when a wave crosses a step function, https://urldefense.proofpoint.com/v2/url?u=https-3A__quantummechanics.ucsd.edu_ph130a_130-5Fnotes_node149.html=DwIGaQ=sJ6xIWYx-zLMB3EPkvcnVg=3u4OCHnAtdypMfYN_K57COVk2XByDoKwnLuc_zRENzE=x11-msafgQ72gWZKP5gGcbCizsHiCDlxxznut2Zo-ug=CV5sXDCtZrDlO2GFM8sW4hec5wD0wT0O34PcltW3ZfI= When the incoming wave exp(ikx) reaches an upwards step function there is a reflected wave R exp(-ikx) and a transmitted wave T exp(ik'x) what this article shows is; 1 + R = T That is, the amplitudes of the incoming wave and the reflected wave add to the amplitude of the transmitted wave If I take this into a square well then I would understand that the waves inside the well have the total amplitude equal to the incoming and transmitted wave. That is, when the wave enters the Muffin Tin the amplitude of wave is not AUGMENTED. So why is this method called "Augmented Plane Wave"? Saludos Pablo ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at https://urldefense.proofpoint.com/v2/url?u=http-3A__zeus.theochem.tuwien.ac.at_mailman_listinfo_wien=DwIGaQ=sJ6xIWYx-zLMB3EPkvcnVg=3u4OCHnAtdypMfYN_K57COVk2XByDoKwnLuc_zRENzE=x11-msafgQ72gWZKP5gGcbCizsHiCDlxxznut2Zo-ug=QELHbpUlFIYdizaiEh0uSI_fcbgFXMcKs25dMRPSkU0= SEARCH the MAILING-LIST at: https://urldefense.proofpoint.com/v2/url?u=http-3A__www.mail-2Darchive.com_wien-40zeus.theochem.tuwien.ac.at_index.html=DwIGaQ=sJ6xIWYx-zLMB3EPkvcnVg=3u4OCHnAtdypMfYN_K57COVk2XByDoKwnLuc_zRENzE=x11-msafgQ72gWZKP5gGcbCizsHiCDlxxznut2Zo-ug=p2zeCI2PUnzFXnYuR6JhoHGW3GZi1dVfbW6410meyh4= ___ Wien mailing list Wien@zeus.theochem.tuwien.ac.at https://urldefense.proofpoint.com/v2/url?u=http-3A__zeus.theochem.tuwien.ac.at_mailman_listinfo_wien=DwIGaQ=sJ6xIWYx-zLMB3EPkvcnVg=3u4OCHnAtdypMfYN_K57COVk2XByDoKwnLuc_zRENzE=x11-msafgQ72gWZKP5gGcbCizsHiCDlxxznut2Zo-ug=QELHbpUlFIYdizaiEh0uSI_fcbgFXMcKs25dMRPSkU0= SEARCH the MAILING-LIST at: https://urldefense.proofpoint.com/v2/url?u=http-3A__www.mail-2Darchive.com_wien-40zeus.theochem.tuwien.ac.at_index.html=DwIGaQ=sJ6xIWYx-zLMB3EPkvcnVg=3u4OCHnAtdypMfYN_K57COVk2XByDoKwnLuc_zRENzE=x11-msafgQ72gWZKP5gGcbCizsHiCDlxxznut2Zo-ug=p2zeCI2PUnzFXnYuR6JhoHGW3GZi1dVfbW6410meyh4= -- Samuel B. Trickey QTP, Depts. of Physics and Chemistry 2324 Physics Building Box 118435 Univ. of Florida Gainesville, FL 32611-8435 Vox: 352-392-6978 (direct) Vox: 352-392-1597 (receptionist) Fax: 352-392-8722 http://www.qtp.ufl.edu/ofdft http://users.clas.ufl.edu/trickey
Re: [Wien] An interesting article on DFT: Understanding density functional theory (DFT) and completing it in practice
Be very careful with this article. The method it presents purports to give a correct set of DFT results - both total energy and band gap - with a prescription for constructing a finite-sized basis set. The explicit contradiction with the concept of the complete basis set limit should be cause for skepticism at the least. peace, Sam On 12/08/2016 08:11 AM, Osama Yassin wrote: Dear Colleague I came across the article: *Understanding density functional theory (DFT) and completing it in practice. **It may be of interest for develpers and users of DFT.* http://scitation.aip.org/content/aip/journal/adva/4/12/10.1063/1.4903408 The article is open for free. Best wishes *_Osama _* *Prof Dr Osama Ali Yassin * */Professor of Solid State Physics and former ICTP regular associate/* */Department of Physics, Faculty of Science/* *Taibah University, A-Madinah Al-Munawarh, Saudi Arabia* ___ 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 -- Samuel B. Trickey QTP, Depts. of Physics and Chemistry 2324 Physics Building Box 118435 Univ. of Florida Gainesville, FL 32611-8435 Vox: 352-392-6978 (direct) Vox: 352-392-1597 (receptionist) Fax: 352-392-8722 http://www.qtp.ufl.edu/ofdft http://users.clas.ufl.edu/trickey ___ 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
