FLEUR input & outputfile
(Please note, that not all documentation covers v0.27)
This you have to specify
 [[input file for the input generator]] or
 The inp file (deprecated in v0.27)
These you have to specify sometimes
 The nocoinp file
 The qpts file
 The plotinfile (deprecated in v0.27)
 The band_inp file
 Other small useful files
 Wannierrelated input and output files
These you can modify
 The enpara file (deprecated in v0.27)
 The kpts file (deprecated in v0.27, replaced by list in inp.xml)
 The sym.out file
 The fl7para file (deleted in v0.27)
 The plot_inp file
Output produced by FLEUR
 The out file
 The DOS.x files
 The dosinp file (deprecated in v0.27)
 The Charge_and_Potential files
 The files produced in a Jij calculation
 Other strange_unformatted files
 Additional files produced in a Hybrid functional calculation
nocoinp
The nocoinp file contains the settings needed for a calculation using NonCollinear Magnetism
Note: This is a fixedformat file, so adhere to the format given below!
atomtype 1,l_relax=F
alpha = 0.0000000000,b_cons_x = 0.0000000000
beta = 1.5707963268,b_cons_y = 0.0000000000
0.0000000000
**********logical parameters******************
l_ss=F,l_mperp=F,l_constr=F,l_disp=F,sso_opt=FFT
mix_b= 0.500
qss=( 1.0000000000, 0.5000000000, 0.0000000000)
qsc=( 10.0000000000, 1.0000000000, 1.0000000000)
 Select the atom type atomtype: clear. l_relax: do you want to relax the direction of the moment localised at atom 1?
 Angles alpha: 1st angle that determines magnetic strucuture. Equal to "phi" in spherical coordinates. b_cons_x: ConstraintField in xdirection. Is determined selfconsistently if l_constr=T.
 Angles beta: "theta" (measured from the z axis) in spherical coordinates. For alpha and beta (lines 23) you can replace the last two digits by 'pi' or 'dg' to indicate that you enter the angles in multiples of Pi or in degrees, thus 'beta = 1.5707963268' is equivalent to 'beta = 0.50000000pi' or 'beta = 90.0000000dg'.

Reserved for future use. For each atomtype these four lines have to be supplied!

empty line. Now the atomtypedependent information is finished.
 Logical switches l_ss=T/F : Spinspiral, if l_ss=T then enter the spiralvector in line 8. l_mperp=T/F : Do you want output of the magnetisation perpendicular to chosen axis (determined by alpha and beta)? l_constr=T/F : Do we constrain the moments or not. So far l_relax and l_constr exclude each other. sso_opt=??? : Three logical switches for (spin spirals + spin orbit).
 Mixing mix_b= : Mixingfactor; if l_constr=T then mixing of Constraintfield in this case mix_b= 0.5 should work fine in case of l_relax=T Mixing of input/outputdirection of moments you can choose mix_b>1 (e.g. 4)
 Spin spiral vector qss : Measured in reciprocal lattice vectors. To each atom with a basis vector τ this will add an angle 2 π (q . τ) to α defined above (line 2).
 [optional] denominator of spin spiral vector: if this line (starting with 'qsc=') is provided, the components of qss are divided by the numbers given here When you want to calculate Heisenberg interaction parameters Jij, you'll need additional switches. This is how nocoinp file looks in this case:
atomtype 1,l_relax=F,l_magn=T,M=2.96337,magtype= 1
alpha = 0.0000000000,b_cons_x = 0.0000000000
beta = 1.5707963268,b_cons_y = 0.0000000000
0.0000000000
**********logical parameters******************
l_ss=T,l_mperp=F,l_constr=F,l_disp=F
mix_b= 0.500,thetaJ= 0.5235987756,nsh= 50
qss=( 0.1000000000, 0.5000000000, 0.0000000000)
 Describe the atomtype
 l_magn: Is this atomtype magnetic?
 M: What is the value of its magnetic moment (don't forget the sign!)?
 magtype: that atoms were formerly in the same type is indicated by the same magtype
 Warning: Angle beta will be taken into account only if l_disp=T (line 6), otherwise it is replaced with the angle thetaJ (line 7)
 The dispersion switch
 l_disp: If l_disp=T, Force theorem is used to calculate the sum of eigenvalues for each qss predefined in qpts file. In this case, Jij parameters are not calculated.
 Cone angle
 thetaJ: The angle used as beta (line 3) in Jij calculations
 nsh: How many shells of neighbours do you want to consider?
 Warning: When l_J=T in the input file, qss defined here is ignored; qss vectors from qpts file are used instead.
qpts
The qpts file contains a list of all spinspiral vectors for a calculation of [[Heisenberg interaction parameters Jij]]. It has the following general format:
281
.0000000000 .0000000000 .0000000000
.4642857143 .4642857143 .4642857143
.3928571429 .4642857143 .4642857143
...
Where
 The first line specifies the total number of qss vectors
 A list of qss vectors follows, where their coordinates are measured in reciprocal lattice vectors
plotin
The plotinfile is the input file for the old chargedensity and potential plotting subroutine. If you do not have no good reasons to stay with this input format it is suggested that you use the new plot_inp file instead.
Example of a file named "plotin":
2Dim=T
Zahl 1
xz_cut test
0.000000 0.000000 19.000000
1.000000 1.000000 19.000000
1.000000 1.000000 19.000000
xPkt 100 yPkt 300
Creates a set of 100x300 charge density values in a plane spanned by the vectors that connect the 3 positions (0,0,19), (1,1,19) and (1,1,19), where the first two coordinate values are given in internal coordinates and the third (zvalue) is in atomic units. The output file will be names zx_cut.
band_inp
The band_inp file is a small input file used in the new bandstructure generation (see: [[Using the new FLEUR mode]]). It just contains a list of points in the Brillouine zone in the following format:
 the first character of the line is the Label of the point (use small letters for Greek symbols)
 the next three numbers are the coordinates of the point in internal coordinates. (For 2D band structures also three numbers have to be given but the last one will be ignored.)
At the Bilbao Crystallographic Server you find the ''k''vectors types for all 230 space groups.
Example:
g 0.0 0.0 0.0
X 0.5 0.0 0.0
M 0.5 0.5 0.0
g 0.0 0.0 0.0
Small useful files
In some cases, small files are used to influence the way, how FLEUR behaves during a run:
qfix
Contains: a logical "T" or "F", to decide, how the charge is normalized, in case this has to be done. If "T" is set (or this file is not present), renormalize the charge everywhere in space, if "F" is read, renormalize only the interstitial charge.
Use: if the atomic positions have been changed, e.g. after a relaxation step, and the last converged charge density is used for the new calculation.
eps_force
Contains: a real, e.g. " 0.0005", to determine, when the convergence of the forces is good enough to make a new input file (inp_new). The default (if this file is not present) is 0.00001 htr/a.u. Use: if the required precision is low, e.g. as long as you employ a steepestdescent algorithm for relaxation.
orbcomp
Contains: an integer, e.g. "3", to find out the atom, where an orbital decomposition should be made. If the DOSflags are not set to DOS=T
and ndir=3
this file is ignored, if the flags are set and no file is present, a layerdecomposition of the DOS is made.
orbcomprot
**Contains: three lines, specifying the Eulerangles {$\alpha, \beta$} and {$\gamma$} to rotate the coordinate frame in which the orbital decomposition (see above) is performed.
apwefl
Contains: input parameters for applied external fields. It consists of one or two lines in free format, the first line contains a real number, specifying the location (in atomic units from the vacuum boundary) of the plane with the external charges as explained in the section on electric fields. The second (optional) line is used to specify the amount of charge that should be placed on this planes, one real number per vacuum (i.e. in case of inversion or zreflection symmetry one number, otherwise two. For the syntax for inhomogeneous fields, read the page about electric fields.
mfee
If present, an additional, external magnetic field is added. The syntax of the file is: One line per atom type; in each line the fixedformat "(i2,1x,f8.5)" is used, i.e. 2 digits for the atom type, space, and 8 digits for the value (in Hartree).
n_mmp_rot
This file allows you to rotate the LDA+U density matrices by some angles (θ, φ) in real space. One line (free format) is reserved for each atom with an "U". The meaning of these angles is the same as in spinorbit coupling mode, i.e. θ is a rotation around the yaxis, φ rotates afterwards around z.
Use: e.g. to stabilize in an open dshell an orbital moment in arbitrary directions, it is convenient to specify the density matrix with the moment along z (more or less diagonal) and then rotate in the required direction.
vca.in
Necessary for the "virtual crystal approximation", i.e. to tune the nuclear number between two integer values to simulate an alloy. E.g. a "element" with Z=25.5 could mean a Mn'x'Fe'(1x)' alloy with x=0.5. The file consists of lines with an integer (for the atomtype) and a float (added or subtracted charge at this atom). E.g. "1 0.5" means that half an nuclear charge should be added at the first atom type. The electronic charge should then be adjusted accordingly to ensure charge neutrality.
enpara
Energy parameters for the linearized radial basisfunction
There are, in principle, three ways to specify the energy parameters. These types are
 The normal "energy" format
 The "simple" nformat
 The floating energy parameters
The normal "energy" format
For each atom type in the input file the linearization energies are given for all lvalues. Additionally you can specify:
 A mixing factor for a simple mixing scheme of these parameters
 Logical switches allowing to fix some parameters
 The skiplo value specifying the number of states considered to be covered by LO's
Depending on your setup you will also find:
 Parameters for both spins
 Energy parameters for the zdependend basis in the vacuum for a film calculation
 Energies for local orbitals
Example (film, 1 atom type, 2 spins, no LO's):
energy parameters for window 1 spin 1 mix= 1.000000
atom s p d f
> 1 0.31794 0.25299 0.21364 0.21967 change: TTTT skiplo: 0
vacuum parameter= 0.22066 change: T second vacuum= 0.22066
energy parameters for window 1 spin 2 mix= 1.000000
atom s p d f
> 1 0.29891 0.21597 0.19182 0.18453 change: TTTT skiplo: 0
vacuum parameter= 0.20192 change: T second vacuum= 0.20192
Another example (film, 2 atom types, 1 spin, 2 LO's):
energy parameters for window 1 spin 1 mix= 1.000000
atom s p d f
> 1 0.26719 0.21434 0.23628 0.20953 change: TTTT skiplo: 4
> lo 2.20113 1.34013
> change T T
> 2 0.25728 0.22454 0.21551 0.22500 change: TTTT skiplo: 4
> lo 2.21847 1.35312
> change T T
vacuum parameter= 0.22516 change: T second vacuum= 0.22516
Notice, that the LO's are one "s" and one "p" orbital, so that for the determination of the valence energy parameters (first line) in total the lowest four energy levels per atom have to be skipped ("skiplo: 4").
The simple nformat
Sometimes, it is tedious to find out the correct ranges for the energy parameters and how many levels have to be skipped for the LO's. Then it might be more convenient to simply give the principle quantum number of the state, you want to treat in your valence window and what should be added as local orbital. One example, how this can be done is shown here:
energy parameters for window 1 spin 1 mix= 1.000000
atom s p d f
> 1 4.00000 4.00000 3.00000 4.00000 change: FFFF skiplo: 4
> lo 3.00000 3.00000
> change F F
This would be the typical setup for an element on the left side in the 3drow, with 4s, 4p, and 3d orbitals (plus 4f, also this has to be specified), and two local orbitals for 3s and 3p. For example Sc would require this kind of setup, maybe also Ti. The integer values of all energy parameters for an atom type indicates, that all parameters for this atom should be determined from an atomic calculation with the actual potential. Also the inputgenerator sets up this kind of files (the "change" flags are set to "F" to keep this format).
Which energy parameters are in the end actually taken for the calculation, you can read from the out file. For the above example (Ti) the program calculates e.g.:
Atom 1 4s branch from 1.78 to 1.61 htr. ; e_l = 0.2179
Atom 1 4p branch from 0.89 to 2.06 htr. ; e_l = 0.3310
Atom 1 3d branch from 9.99 to 0.51 htr. ; e_l = 0.3247
Atom 1 4f branch from 9.99 to 2.64 htr. ; e_l = 0.6168
Atom 1 3s branch from19.22 to 1.75 htr. ; e_l = 1.7786
Atom 1 3p branch from15.82 to 0.86 htr. ; e_l = 0.8986
this corresponds to an enparafile in the "energy format":
energy parameters for window 1 spin 1 mix= 1.000000
atom s p d f
> 1 0.21790 0.33100 0.32470 0.61680 change: TTTT skiplo: 4
> lo 1.77860 0.89860
> change T T
The program will set the enparafile back to this format, if you change the F's to T's, to allow an update of the enparafile.
Please note, that this format causes problems if it is used with very light atoms, e.g. H, since the 4fparameter cannot be determined (for some MTradii, no bound state can be found).
The floating energy parameters
Another possibility to specify the energy parameters is, to reference them to a certain value of the radial potential in the muffintin (at 1/4 of the distance to the MTradius). While this has of course the disadvantage, that energy parameters cannot be simply transfered from one muffintin radius to the other, the energy parameters are more stable with respect to strong fluctuations of the potential, as occurs e.g. at the beginning of the SCF cycle. This can be toggled by setting a switch in the [[input]]file (inp, line 26 in the example) from 0 to 1. An example (like above, for Ti) would be:
energy parameters for window 1 spin 1 mix= 0.300000
atom s p d f
> 1 9.10093 9.15589 9.17100 9.18091 change: TTTT skiplo: 4
> lo 7.13609 8.00391
> change T T
The reference value (potential in the muffintin) can be found in the outfile:
Reference energies for energy parameters
spin 1, atom type 1 = 8.870484 r= 0.64167
adding this value to the floating energy parameters gives you back the normal "energy format", very similar to the values of the last section.
kpts
The kptsfile contains a list of all kpoints. You have to specify a kptsfile or use the inbuild kpoint generator.
It has the following general format:
2 140.0000000000
13.00000 14.00000 15.00000 8.00000
....
Where
 the first line specifies the total number of kpoints (here 2) and a scaling factor (here 140.0).
 the following lines give the (x,y,z) values of the kpoint (here 13.0/140.0, 14.0/140.0 15.0/140.0) and its relative weight. The total weight is simply obtained by summing up all the relative weights.
Notes:
 Instead of creating the file by yourself, FLEUR can generate it for you, using the parameters in the [[input]] file.
 If you switch to another kpoint set, make sure to use the proper value for nkptd in file [[fl7para]], or delete it in order to make FLEUR recreate it with default values.
 In case of a 2Dcalculation for a [[filmsetup]]. Only the (x,y) coordinates are given and the weight is in place of the zcolumn
 If you set tria=T (which is very useful for obtaining good [[Density of states]]) the [[kpoint generator]] will generate additional information at the end of the file.
sym.out
Despite its name, this is an input file for FLEUR. It contains the symmetry information generated by the inp file generator (hence its name :) ). You probably should never edit it!
fl7para
The file fl7para is read in the very beginning of a FLEUR run and contains the dimension parameters of the arrays that are to be allocated. Each value is paired with the variable name in FLEUR, and preceded by a line of brief explanation. If not existent at program startup, it will be created automatically with reasonable default values, a lot of which are constructed out of the statements in the input file.
Note that newer versions of Fleur do not automatically generate an fl7para file. If you want to modify values controlled by the fl7para file, you can create a fl7para file using the template from the out file.
Notes
 It is a fixed format file, edit with care.
 In many cases you do not need to touch this file.
 One of the other cases is when you need more unoccupied states: increase neigd then.
 Other examples include the case when you increase values in the input file. Then you need to increase to proper dimensions in fl7para accordingly.
plot_inp
The plot_inp file defines the parameters used to generate a charge density plot (parameter iplot=t
in the inp file).
Example file:
2,xsf=t
&PLOT twodim=t,cartesian=t
vec1(1)=10.0 vec2(2)=10.0
filename='plot1'
/
&PLOT twodim=f,cartesian=f
vec1(1)=1.0 vec1(2)=0.0 vec1(3)=0.0
vec2(1)=0.0 vec2(2)=1.0 vec2(3)=0.0
vec3(1)=0.0 vec3(2)=0.0 vec3(3)=1.0
grid(1)=30 grid(2)=30 grid(3)=30
zero(1)=0.0 zero(2)=0.0 zero(3)=0.5
filename ='plot2'
/
The first line specifies the no of plots to generate (2) and the output format. Setting xsf
to true will generate output for the XCrysDen visualisation program.
The parameters of each plot are given in a namelist input below. The following set of input variables can be specified:
twodim=t/f
: twodimensional or threedimensional plot.cartesian=t/f
: are the vectors given in cartesian or internal coordinates.vec1
,vec2
,vev3
: The vectors spanning the plotting plane/volume. All components of these vectors default to 0.0, so that you have to give only the nonzero elements. For a 2D plot onlyvec1
andvec2
are used.zero
: A vector shifting the origin of the plot volume, i.e. the corner from which vec1,vec2,vec3 are measured (defaults to (0.0,0.0,0.0)).grid
: A integer vector specifying the grid size (two/three values for 2D/3D plots). All grid sizes default to 100. filename: A name for the file to store the data, or for the dataset in the xsf file.
There are additional options concerning '''noncollinear magnetization''':
1,xsf=t,polar=t
&PLOT phi0=0.5 unwind=t
...
polar=t/f
: In the casepolar=t
, additional files are created that allow to plot the magnetization in terms of absolute value ('mabs') and angles theta,phi ('mtha','mphi'). The default isf
, the statementpolar=f
can be skipped. Note, thatpolar
is not part of the namelist input.phi0
: In the casepolar=t
,phi0
specifies the range of the azimuth angle phi: phi is given in the interval [phi0
pipi,phi0
pi+pi]. The default isphi0=
0.0.unwind=t/f
: Relevant for spinspiral plots. In the caseunwind=t
, the plot shows {$ {\rm m}{\rm plot}({\rm r})= {\rm R}{{\rm q} . {\rm r}}\,{\rm m}({\rm r}) $}, i.e. the plot shows the magnetization rotated by the angle q.r. In this case, the plotted {$ {\rm m}_{\rm plot} $} is periodic in the computational unit cell.
out
The out
file is the basic output file generated by the fleur
code. \
It contains a huge amount of information, normally it is not necessary to \
go through this file in detail, but in case of errors and problems it is in \
most cases useful to refer to this file.
The overall layout of this file is:
 a repetition of the input parameters
 symmetry information (stars & lattice harmonics)
 for each iteration:
 multipoles, potentialdensity integrals
 wavefunction parameters
 eigenvalues for each kpoint
 Fermi level
 partial charges & energy parameters
 corelevels
 magnetic moments, if any
 inputoutput charge density distance
If you compile fleur.x
with DCPP_HTML
, you get a more structures, htmlformated version of this file.
When you set up the starting density, you will also obtain atomic levels of your constituent atoms in the outfile, e.g.
n kappa l j occ. eigenvalue (har) <r>
spin No. 1
1 1 0 0.5 2.00 3324.468879 0.015793
2 1 0 0.5 2.00 596.793964 0.065786
2 1 1 0.5 2.00 573.528807 0.053891
2 2 1 1.5 4.00 488.314248 0.062935
3 1 0 0.5 2.00 143.977036 0.171090
3 1 1 0.5 2.00 133.441852 0.161585
3 2 1 1.5 4.00 114.369584 0.178084
3 2 2 1.5 4.00 97.056332 0.154532
3 3 2 2.5 6.00 93.010528 0.159518
4 1 0 0.5 2.00 32.992819 0.377147
4 1 1 0.5 2.00 28.414446 0.377905
4 2 1 1.5 4.00 23.706774 0.412847
4 2 2 1.5 4.00 16.248825 0.416371
4 3 2 2.5 6.00 15.370478 0.427488
4 3 3 2.5 6.00 5.679662 0.438154
4 4 3 3.5 8.00 5.477905 0.444295
5 1 0 0.5 2.00 5.745394 0.829854
5 1 1 0.5 2.00 4.149632 0.883427
5 2 1 1.5 4.00 3.230129 0.974662
5 2 2 1.5 4.00 1.013890 1.215674
5 3 2 2.5 6.00 0.903410 1.261554
6 1 0 0.5 2.00 0.512439 2.182490
6 1 1 0.5 2.00 0.205150 2.715903
6 2 1 1.5 1.00 0.132442 3.073088
(here for Bi). This might help to see, which states are well localized
(low energy and small radial extension
dosx
(DOS.1 and DOS.2)
(100(1x,e10.3)) e,totdos,interstitial,vac1,vac2,(at(i),i=1,ntype),((q(l,i),l=1,LMAX),i=1,ntype)
where
 e is the energy in eV (= 1/27.2 htr)
 at(i) is the local DOS of a singe atom of the i'th atomtype and
 q(l,i) is the lresolved DOS at the i'th atom.
Please note, that in the case of spinorbit coupling (and generally noncollinear) calculations a well defined separation of spinup/spindown is only possible in the muffin tin spheres. Therefore, only these values will differ in the DOS.1/2 files. The interstitial DOS is always calculated as total DOS minus the sum of the muffintin contributions (times number of equivalent species in the atom type).