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determination of Exchange coupling parameter Date: 2020/11/23 04:44 Name: reza   <majidiniareza@gmail.com> Hi to all. In the calculation of the exchange coupling parameter for the Fe bulk case, a config file is used. in part of <ij paires.cellid Why are the same indices used for i and j? And how are other indices determined? Is it possible to explain by figure what atoms these numbers correspond to? thanks a lot

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Re: determination of Exchange coupling parameter ( No.1 ) Date: 2020/12/03 10:49 Name: Seungjin Kang  <gsj37@snu.ac.kr> The first two indices are for the atom index defined in Atoms.SpeciesAndCoordinates section. Then the following three integers refer the Bravais lattice index. So if you set, [1 3 1 1 0], this means that you are calculating the exchange coupling between first atom in [0 0 0] cell and third atom in [1 1 0] cell. Re: determination of Exchange coupling parameter ( No.2 ) Date: 2020/12/06 00:13 Name: reza  <majidiniareza@gmail.com> hello Mr.kang thanks a lot for your reply. As I understand it, it is only possible to calculate the exchange coupling parameter between two atoms of different unit cells and not two atoms of one unit cell. Is there a way to calculate the exchange coupling parameter between two atoms of a single unit cell? thanks a lot. Re: determination of Exchange coupling parameter ( No.3 ) Date: 2020/12/07 09:19 Name: Seungjin Kang  <gsj37@snu.ac.kr> >> Is there a way to calculate the exchange coupling parameter between two atoms of a single unit cell? You can just set the cell index to be [0 0 0]. ex) Exchange parameter between atom 1 and atom 4 in the same cell: [1 4 0 0 0] Exchange parameter between atom 1 and atom 2 in the same cell: [1 2 0 0 0] Re: determination of Exchange coupling parameter ( No.4 ) Date: 2020/12/22 07:14 Name: reza  <majidiniareza@gmail.com> Hello Mr. Kang I have questions about determining the exchange coupling parameter and use of them in determining curie temperature. I am studying the effect of Mn impurities on the magnetic properties of GaFeO3. the used input file is given below. 1 Ga 1.28066 9.38418 0.88738 6.5 6.5 off 2 Ga 7.43807 4.67018 4.17712 6.5 6.5 off 3 Ga 3.04057 9.38419 3.44838 6.5 6.5 off 4 Ga 5.67816 4.67019 1.61608 6.5 6.5 off 5 Ga 1.38022 2.85354 4.11797 6.5 6.5 off 6 Ga 7.33849 7.56756 0.94650 6.5 6.5 off 7 Ga 2.94099 2.85354 1.55696 6.5 6.5 off 8 Ga 5.77773 7.56756 3.50751 6.5 6.5 off 9 Fe 1.29944 5.45554 0.94921 9 5 off 10 Fe 7.41927 0.74155 4.11527 9 5 off 11 Fe 3.02180 5.45553 3.51022 9 5 off 12 Fe 5.69694 0.74153 1.55427 9 5 off 13 Fe 0.25846 7.47108 3.44746 5 9 off 14 Fe 8.46030 2.75713 1.61699 5 9 off 15 Fe 4.06277 7.47104 0.88644 5 9 off 16 Fe 4.65593 2.75709 4.17801 5 9 off 17 O 2.81474 3.97881 4.98049 3 3 off 18 O 5.90399 8.69286 0.08385 3 3 off 19 O 1.50641 3.97879 2.41946 3 3 off 20 O 7.21217 8.69290 2.64483 3 3 off 21 O 4.23188 4.03270 2.58837 3 3 off 22 O 4.48676 8.74669 2.47600 3 3 off 23 O 0.08933 4.03275 0.02736 3 3 off 24 O 8.62943 8.74675 5.03700 3 3 off 25 O 8.75954 1.84244 3.30464 3 3 off 26 O -0.04086 6.55641 1.75979 3 3 off 27 O 4.35660 1.84236 0.74363 3 3 off 28 O 4.36214 6.55633 4.32081 3 3 off 29 O 1.37497 1.83009 0.74846 3 3 off 30 O 7.34377 6.54412 4.31594 3 3 off 31 O 2.94622 1.83010 3.30948 3 3 off 32 O 5.77246 6.54411 1.75496 3 3 off 33 O 1.46273 6.32215 4.31628 3 3 off 34 O 7.25601 1.60819 0.74814 3 3 off 35 O 2.85852 6.32211 1.75530 3 3 off 36 O 5.86016 1.60815 3.30913 3 3 off 37 O 1.45280 8.81816 2.63396 3 3 off 38 O 7.26594 4.10423 2.43045 3 3 off 39 O 2.86840 8.81810 0.07294 3 3 off 40 O 5.85026 4.10422 4.99147 3 3 off Atoms 9 to 12 are Fe1, and atoms 13 to 16 are Fe2. the simulation was carried out on unit cell containing 40 atoms. I have calculated exchange coupling parameter between atoms 9 and 15 and the value 58.42 meV without negative was obtained. M.J.Han et al. in an article entitled " magnetic ordering and exchange interactions in multiferroic GaFeO3 " reported the value -105.75 in units of kelvin for exchange interaction parameter between Fe1 and Fe2 atoms.is there a relation between these two values&#1567; And another question is about determining the curie temperature in GFO and Mn-doped GFO. I recently read an article entitled " Efficient Algorithm Based on Liechtenstein Method for Computing Exchange Coupling Constants Using Localized Basis Set'. This article discusses the calculation of the curie temperature. But I have trouble using this relation to determine the curie temperature. Thanks for the valuable tips.

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