Hi Joshua, I can not find convergence on the absorption spectra. It is very hard to believe that 500 atoms is not enough to find a converged spectra. If I increase the broadening for the LDOS, the default is 0.1eV for the one exported by Arthemis and 0.2eV is shown in the manual, the last one is still small compared with 4.16 eV. Which is a good criteria to choose it and where I can find the core hole broadening value? I will quit the LDOS card to obtain results faster, but pot.bin will be generated anyway (I will leave the CONTROL card option on), if not, is it needed for another calculation? The calculations (without the LDOS) and the spectra will be obtained like before? I will implement the lanczos algorithm too and parameter nex to obtain faster results with a bigger number of atoms. Cheers, euG 8<- - - - - - 8<- - - - - - 8<- - - - - - 8<- - - - - - Lic. Eugenio H. Otal E-mail: eotal@citefa.gov.ar eugenioh@gmail.com 8<- - - - - - 8<- - - - - - 8<- - - - - - 8<- - - - - - Hi Eugenio, I have a question for you, When you say that convergence is not reached, do you mean convergence of the absoption spectrum or convergence of the LDOS? These are very different since the absorption has core-hole and self-energy broadening included. I noticed that you use 0.1 eV broadening for the LDOS, which is much smaller than the core hole broadening which is 4.16eV. Also, the calculation will be much quicker if you do not run LDOS since FEFF does the matrix inversion for each unique potential and energy when the LDOS card is present. Otherwise, the inversion is only done for the central atom potential at each energy. Cheers, Josh Kas

Bruce,

thanks for your answer, it is a great problem to increase the number of atoms, huge CPU time is needed to finish a calculation.

Here I pasted the header and the first lines of the atom list and attached the whole file, if somebody could help me to reduce the calculation time I will be grateful.

Thanks in advance, euG

* This feff8 input file was generated by Artemis 0.8.011 * Atoms written by and copyright (c) Bruce Ravel, 1998-2001

TITLE name: ZnO:Er 1 at no distortion d= 4.136 TITLE formula: ZnO TITLE sites: Zn1,O1 TITLE refer1: wyckoff, vol 1, ch III, p 111 TITLE refer2: TITLE schoen: TITLE notes1:

* Er L3 edge energy = 8358.0 eV EDGE L3 S02 1.0

* pot xsph fms paths genfmt ff2chi CONTROL 1 1 1 1 1 1 PRINT 3 0 0 0 0 0

*** ixc=0 means to use Hedin-Lundqvist * ixc [ Vr Vi ] EXCHANGE 0

*** Radius of small cluster for *** self-consistency calculation *** A sphere including 2 shells is *** a good choice *** l_scf = 0 for a solid, 1 for a molecule * r_scf [ l_scf n_scf ca ] SCF 4.0

*** Upper limit of XANES calculation. *** This *must* be uncommented to *** make Feff calculate full multiple *** scattering rather than a path expansion * kmax [ delta_k delta_e ] XANES 4.0

*** Radius of cluster for Full Multiple *** Scattering calculation *** l_fms = 0 for a solid, 1 for a molecule * r_fms l_fms FMS 5.00 0

*** Energy grid over which to calculate *** DOS functions * emin emax eimag LDOS -30 20 0.1

*** for EXAFS: RMAX 12.0 and uncomment *** the EXAFS card RPATH 0.1 *EXAFS 20

POTENTIALS * ipot Z element l_scmt l_fms stoichiometry 0 68 Er 3 3 0.001 1 30 Zn 2 2 2 2 8 O 1 1 2 3 68 Er 3 3 2

ATOMS * this list contains 902 atoms * x y z ipot tag distance 0.00000 0.00000 0.00000 0 Er 0.00000 0 -0.93804 -1.62473 -0.49466 1 Zn1 1.94019 1 1.87611 0.00002 -0.49466 1 Zn1 1.94023 2 -0.93804 1.62477 -0.49466 1 Zn1 1.94023 3 -0.93804 -1.62473 1.30173 2 O1 2.28346 4 0.93804 1.62473 -1.30173 2 O1 2.28346 5 1.87611 0.00002 1.30173 2 O1 2.28348 6 -0.93804 1.62477 1.30173 2 O1 2.28348 7 -1.87611 -0.00002 -1.30173 2 O1 2.28348 8 0.93804 -1.62477 -1.30173 2 O1 2.28348 9 0.93804 1.62473 2.10879 1 Zn1 2.82253 12 -1.87611 -0.00002 2.10879 1 Zn1 2.82255 13 0.93804 -1.62477 2.10879 1 Zn1 2.82255 14 0.93804 1.62473 -3.09811 1 Zn1 3.62187 21 -1.87611 -0.00002 -3.09811 1 Zn1 3.62189 22 0.93804 -1.62477 -3.09811 1 Zn1 3.62189 23 -3.75219 0.00002 -0.49466 1 Zn1 3.78466 24 1.87611 -3.24948 -0.49466 1 Zn1 3.78465 25 1.87611 3.24952 -0.49466 1 Zn1 3.78469 26 -3.75219 0.00002 1.30173 2 O1 3.97158 27 1.87611 -3.24948 1.30173 2 O1 3.97158 28 -1.87611 3.24948 -1.30173 2 O1 3.97158 29 3.75219 -0.00002 -1.30173 2 O1 3.97158 30 1.87611 3.24952 1.30173 2 O1 3.97161 31 -1.87611 -3.24952 -1.30173 2 O1 3.97161 32 2.81415 1.62475 2.60345 3 Er 4.16380 33 -1.87611 3.24948 2.10879 1 Zn1 4.30417 45 3.75219 -0.00002 2.10879 1 Zn1 4.30418 46