{"title":"非常高温Kohn-Sham DFT模拟的要求以及如何绕过它们","authors":"A. Blanchet, M. Torrent, J. Clérouin","doi":"10.1063/5.0016538","DOIUrl":null,"url":null,"abstract":"In density functional high temperature simulations (from tens of eV to keV) the total number of Kohn-Sham orbitals is a critical quantity to get sound results. The occupation of the highest orbital in energy is here derived from the properties of the homogeneous electron gas, which gives a prescription on the total number of orbitals to reach a given level of occupation. Very low levels of occupation (10-5 to 10-6) must be considered to get convergence with Kohn-Sham orbitals, making high temperature simulations unreachable beyond a few tens of eV. After testing these predictions against ABINIT oftware package results, we test the implementation of the Extended method of Zhang et al. [PoP 23 042707, 2016] in the ABINIT package to adress very high temperatures by bypassing these strong orbital constraint.","PeriodicalId":8424,"journal":{"name":"arXiv: Computational Physics","volume":"6 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2020-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"19","resultStr":"{\"title\":\"Requirements for very high temperature Kohn–Sham DFT simulations and how to bypass them\",\"authors\":\"A. Blanchet, M. Torrent, J. Clérouin\",\"doi\":\"10.1063/5.0016538\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"In density functional high temperature simulations (from tens of eV to keV) the total number of Kohn-Sham orbitals is a critical quantity to get sound results. The occupation of the highest orbital in energy is here derived from the properties of the homogeneous electron gas, which gives a prescription on the total number of orbitals to reach a given level of occupation. Very low levels of occupation (10-5 to 10-6) must be considered to get convergence with Kohn-Sham orbitals, making high temperature simulations unreachable beyond a few tens of eV. After testing these predictions against ABINIT oftware package results, we test the implementation of the Extended method of Zhang et al. [PoP 23 042707, 2016] in the ABINIT package to adress very high temperatures by bypassing these strong orbital constraint.\",\"PeriodicalId\":8424,\"journal\":{\"name\":\"arXiv: Computational Physics\",\"volume\":\"6 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2020-08-24\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"19\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv: Computational Physics\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1063/5.0016538\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv: Computational Physics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1063/5.0016538","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Requirements for very high temperature Kohn–Sham DFT simulations and how to bypass them
In density functional high temperature simulations (from tens of eV to keV) the total number of Kohn-Sham orbitals is a critical quantity to get sound results. The occupation of the highest orbital in energy is here derived from the properties of the homogeneous electron gas, which gives a prescription on the total number of orbitals to reach a given level of occupation. Very low levels of occupation (10-5 to 10-6) must be considered to get convergence with Kohn-Sham orbitals, making high temperature simulations unreachable beyond a few tens of eV. After testing these predictions against ABINIT oftware package results, we test the implementation of the Extended method of Zhang et al. [PoP 23 042707, 2016] in the ABINIT package to adress very high temperatures by bypassing these strong orbital constraint.