Questaal Data files and their Formats
Table of Contents
 Table of Contents
 Introduction
 Standard data formats for 2D arrays
 Site files
 The qpts file
 File formats for kpoint lists
 The basp file
 The wkp file
 The save file
 The spf file
 The dos file
 The smpot0 file
 The socscl file
 Selected files generated by lmf or lm for optics
 Selected files generated by lmgf or lmpg
 Selected files generated by the GW codes
 Selected files read or generated by lmfgws
 Selected files read or generated by lmfdmft
Introduction
Questaal codes require a wide variety of data formats to meet the diverse range of purposes they serve. When files are not too large they are usually written in ASCII format. In many cases, such files are passed through the file preprocessor before being scanned for data. The preprocessor’s facilities (e.g. to evaluate expressions and to make looping constructs) can be useful in many contexts.
The preprocessor can modify the input before it is parsed for data. Note also:
 Lines which begin with ‘#’ are comment lines and are ignored. (More generally, text following a `#’ in any line is ignored).
 Lines beginning with ‘%’ are directives to the preprocessor.
Standard data formats for 2D arrays
Many Questaal programs, for example the fplot utility and electronic structure programs such as lm, read files containing 2D arrays. Most of the time they follow a standard format described in this section.
Where possible, the 2D array reader uses rdm.f, so that the files are read in a uniform style. Unless told otherwise, the reader treats data as algebraic expressions. Thus you can use expressions in these files, in addition to expressions in curly brackets {…} managed by the preprocessor.
The array reader must be given information about the number of rows and columns in the file. (They are called nr and nc here.)
The safest way to specify nr and nc is to indicate the number of rows and columns in the first line of the file, as illustrated in the code snippet below (this is the beginning of chgd.cr used in an fplot exercise). nr and/or nc (the number of rows and columns) can be stipulated in the file as shown in the first line of chgd.cr:
% rows 101 cols 101
0.0570627197 0.0576345670 0.0595726102 0.0628546738
...
Note: % rows...
is not a preprocessor directive because rows is not a keyword the preprocessor recognizes.
The reader attempts to work out nr and nc in the following sequence:
 The reader checks to see whether the first nonblank, nonpreprocessor directive, begins with
% ... rows nr
or% ... cols nc
.
If either or both are supplied to set nr and/or columns to nc are set accordingly. In some cases nr or nc is known in advance, for example a file containing site positions has nc=3. In such case the reader is told of the dimension in advance; if redundant information is given the reader checks that the two are consistent.
If they are not, usually the program aborts with an error message.
 In some cases nr or nc is known in advance, for example a file containing site positions has nc=3. In such case the reader is told of the dimension in advance; if redundant information is given the reader checks that the two are consistent.
 If nc has not been stipulated, the parser will count the number of elements in the first line containing data elements, and assign nc to it.
For the particular file chgd.cr, the reader would incorrectly infer nc=4: so nc must be stipulated in this case.  If nr has not been stipulated in some manner, the reader works out a sensible guess from the file contents.
If it knows nc, the reader can count the total number of values (or expressions more generally) in the file and deduce nr from it.
If the number of rows it deduces is not an integer, a warning is given.
Complex arrays
If the array is complex, the first line should contain complex, e.g.
% ... complex
The entire real part of the array must occur first, followed by the imginary part.
Site files
Site files can assume a variety of formats. Their structure is documented here.
The qpts file
This file may be used to read a list of k points for Brillouin zone integration, in lieu of generating them via specifications in the BZ category. (You can generate this file using putqp).
The standard format for this file is
nqp=nqp; nkabc=n1,n2,n3; lshft=sh1,sh2,sh3; ntet=ntet
#
1 q_x(1) q_y(1) q_z(1) w(q_1)
... ... ... ... ...
nqp q_x(nqp) q_y(nqp) q_z(nqp) w(q_nqp)
#
1 idtet(1,1) idtet(2,1) idtet(3,1) idtet(4,1) idtet(5,1)
... ... ... ... ... ...
ntet idtet(1,ntet) idtet(2,ntet) idtet(3,ntet) idtet(4,ntet) idtet(5,ntet)
Lines beginning with # are ignored.
The first line declares dimensions used to generate the file: nqp is the number of qpoints in IBZ, nkabc is the token &THINSP;NKABC&THINSP;, lshft has the same meaning as the token BZJOB , ntet is the number of tetrahedra for each microcell in irreducible Brillouin zone.
Next come the list of k points, together with the k point weights.
Next come information about tetrahedra: the second column is the number of occurences of the tetrahedron, the final four columns point to the corners of the tetrahedra. This latter is not required, but if it is not present, you cannot perform integrations using the tetrahedron method.
File formats for kpoint lists
kpoints and which energy bands or quasiparticles are to be generated are specified in one of three types, or modes.

(default) symmetry line mode is designed for plotting energy bands along symmetry lines. In this case kpoints are specifed by a sequences of lines with start and end points. The output is a bands file in a specially adapted format.

List mode is a general purpose mode to be used when energy levels are sought at some arbitrary set of kpoints, specified by the user. Data is written in a standard format with kpoints followed by eigenvalues.

Mesh mode is a mode that generates states on a uniform mesh of kpoints in a plane. Its purpose is to generate contour plots of constant energy surfaces, e.g. the Fermi surface. Data file output is written in a special mode, with levels for a particular band at all k written as a group.
Symmetry line mode
This is the default mode. See here for a tutorial using this mode. The kpoints file consists of a list of symmetry lines and the number of kpoints in each line. Each line of text in the file specifies one symmetry line with the syntax
#pts startk endk
startk and endk each consist of three numbers specifying a kpoint. You can terminate the list with a line beginning with 0. For example:
51 0 0 0 0 0 1 51 0 0 1 0 .5 .5 0 0 0 0 0 0 0
bnds file, output from symmetry line mode
Bands are written to file bnds.ext in a format specially tailored to symmetry lines.
The file begins with
36 0.02136 2 col= 5:9,14:18 col2= 23:27,32:36 41 ← number of points on this line 0.50000 0.50000 0.50000 ← first k point ↓ energy levels 4.3011 4.2872 4.2872 0.6225 0.4363 0.4363 0.2342 0.2342 0.1355 0.1484 0.9784 1.2027 1.2027 1.7702 1.7702 1.8940 2.3390 2.3390 2.4298 2.9775 2.9775 3.0605 3.1020 3.1020 3.6589 3.7134 4.1113 4.1494 4.1494 4.6987 5.3267 5.3267 5.6162 5.6162 5.9457 6.4435 6.4435 8.6484 8.6484 10.1458
The header line consists of the (maximum) number of bands (36); the Fermi level (0.02136); and the number of color weights (2). The remainder of the line is for informational purposes only and is not needed.
Next follow data for each symmetry line, one line after the other. The data structure for a single symmetry line has this form:
 A line with specifying the number of points for the current symmetry line. Next follow for each point i:
 a line containing k_{i} (3 numbers).
 one or more lines with the energy levels for k_{i}
 If color weights are present, information about color weights, consisting of
 a line containing k_{i} (3 numbers) (should be the same as (1))
 one or more lines with the color weights (should have the same format as (2)
 If a second set of color weights is present, there are lines similar to (3).
 If in a spinpolarized calculation with both spins present, the same information (14) is written for the second spin.
Making figures, symmetryline mode
Use plbnds to read this file format. It can generate directly a (not very pretty) picture rendered in postscript. Better, plbnds can generate data files and a script for the Questaal graphics tool fplot. plbnds generates energy bands in a simple to read, standard Questaal format. You can use fplot or your favorite graphics package.
List mode
This mode is specifed by, e.g. command line argument band~qp. Use this mode to generate energy levels for a discrete list of kpoints. The kpoints file consists of a list of points in standard Questaal format, e.g.
.01 0 0 0 0 0 .01 0 0
This file must have 3 columns, corresponding to the x,y,z, components of k. Unless you specify otherwise the number of rows in the array are the number of k points.
Alternative file format for kpoints specification
There is an alternative format available for this mode: it is the format automatically generated if BZ_PUTQP is set or if the commandline switch –putqp is present.
When this switch is set, lm (or similar programs that do numerical integrations over the Brillouin zone) will save information about the kpoints it uses for integration to file qpts.ext. List mode can read this format; there is some flexibility in the format also. As a minimum the first line should consist of nkp=#, which specifies the number of kpoints in the file. Then follows a list of kpoints, e.g.
nkp=2 1 0.100000000000D+00 0.000000000000D+00 0.000000000000D+00 2 2.600000000000D01 2.500000000000D01 2.500000000000D01
The kpoints file reader will automatically distinguish between these formats.
bnds file, output from list mode
Bands are written in standard Questaal format, used, e.g. by the matrix calculator mcx. The first three columns are the k point; the remaining columns are the bands. If color weights are specified, an additional group of columns are appended.
Plotting, list mode
Because the kpoints need not follow any particular pattern, there is no generic plotting scheme. As noted, the file is in standard Questaal format which can be easily read by programs such as MATLAB.
Additional options, list mode
The list mode has additional suboptions, that make it convenient to collate distinct groups of kpoints into a single list. Switch
band~qp~...
may be extended with any of these switches:
band~qp[,inc=expr][,merge=fnam][,save=fnam]~...
 [,inc=expr] causes the list reader to parse each kpoint, and exclude those for which expr is zero. expr is an ASCII string containing an algebraic expression. expr can (and is expected to) contain kpoint specific variables, which include:
iq kpoint index qx k_{x} qy k_{y} qz k_{z} q k=[k_{x}^{2}+k_{y}^{2}+k_{z}^{2}]^{1/2}
The expression should be integer (returning 0 or nonzero). Example: –band~qp,inc=q<1/2
In this case only kpoints read from the file whose magnitude is less than 0.5 will be retained. 
[,merge=fnam] causes the list reader to read a second file fnam.ext (in standard Questaal format and append the list read from it to the original list.
 [,save=fnam] causes the list reader to write the final kpoints list to fnam.ext. After writing this file the program automatically stops.
Mesh mode
In this mode kpoints are generated on a uniform 2D mesh, useful for contour plots. Invoke with
band~con~...
The mesh is specified by a file containing lines of the form
v_{x} range n_{x} v_{y} range n_{y} height band
where:
 v_{x} and v_{y} are two reciprocal lattice vectors defining a plane
 range is a pair of numbers marking starting and ending points along each vector
 n_{x} and n_{y} are the number of divisions along the first and second vectors
 height specifies the offset normal to the plane
 band specifies which band is to be saved.
Example:
1 0 0 1 1 51 0 1 0 1 1 51 0.00 4,5
bnds file, output from mesh mode
Bands are written in standard Questaal format used by matrix calculator mcx and the graphics package fplot. The number of rows is the number of divisions in the first vector; the number of columns is the number of divisions in the second vector. No k point information is written (it is implicit in the uniform mesh).
Plotting, mesh mode
See this example.
Transformation of the supplied kpoints
The kpoints as supplied from the input file can be transformed.
This is useful in several contexts. If spinorbit coupling is present on the bands depend on the relative orientation of the coordinate system and spin quantization axis (the z axis by default).
In an angleresolved photoemission experiment, $\mathbf{k}$ normal to the surface $\mathbf{k_\perp}$ is modified on exiting the surface, whereas $\mathbf{k_\parallel}$ is conserved. This means that $\mathbf{k}$ measured by ARPES slightly different from $\mathbf{k}$ calculated from the band structure. The larger the kinetic energy the smaller the effect, but in typical photoemission experiments it is not negligible.
There are two ways to transform the $\mathbf{k}$ point. The first is to use the ~rot options to the band switch. The second expressions which you specify in the first line of the kpoints input file. This line consists of a sequence of algebraic expressions, which generate one or more of k_{x}, k_{y}, or k_{z}, which modifies one of more of the Cartesian components of $\mathbf{k}$.
To modify k_{x}, k_{y}, or k_{z} insert a line at the beginning of the file. The first character must be a ’%’, followed by one or more strings with algebraic expressions defining the x, y, and z components of the modified q:
% [var=expr var=expr ...] kx=expr ky=expr kz=expr
kx, ky, kz are the Cartesian coordinates of the modified kpoint. expr are algebraic expressions involving these variables:
qx k_{x} qy k_{y} qz k_{z} q k=[k_{x}^{2}+k_{y}^{2}+k_{z}^{2}]^{1/2}
The expression should be integer (returning 0 or nonzero). Example: let qx, qy, qz, q be the Cartesian components and absolute value of the unmodified kpoint. Any of the kx=expr ky=expr kz=expr may be present; any missing component will be left unchanged from its original value.
This example (in symmetry line mode) modifies k_{x} such that the kinetic energy is increased by 0.1^{2} a.u.
% map kx=(q^2+.1^2qy^2qz^2)^.5 41 .5 .5 .5 0 0 0 L to Gamma ...
You should verify that code reading the kpoints modified the q points by inspecting the output. It should contain the following lines:
suqlst: map qp using the following: kx=(q^2+.1^2qy^2qz^2)^.5
The ~rot option may be used in conjuction with the modification through alegbraic expresssions. For example suppose you want to modify $k_\perp$ normal to the (1,1,0) direction, while preserving $k_\parallel$ in the (1,1,0),(0,0,1) plane.
Take Cu as a concrete example. If lm is your toplevel directory, set up the calculation for Cu with
~/lm/fp/test/test.fp cu 1
This should set up a selfconsistent potential for Cu and save generate energy bands in file bnds.cupwmode11.
The input file as constructed uses the normal Cartesian coordinates for a cube. But if you invoke lmf with vrot=t, viz
lmf vrot=t cu showp
you will see that tag STRUC_ROT=z:pi/4 appears in the preprocessed input file. This tells lmf to rotate the crystal axes, the basis vectors, and the symmetry group operations. This rotates (1/2,1/2,0) to the z axis. Do the following:
$ lmf vrot=t cu quit=ham
and you should see:
Lattice vectors: Transformed to: 0.0000000 0.5000000 0.5000000 0.1035534 0.6035534 0.3535534 0.5000000 0.0000000 0.5000000 0.6035534 0.1035534 0.3535534 0.5000000 0.5000000 0.0000000 0.0000000 0.0000000 0.7071068
Run the band calculation exactly as was done in the test case, but modify it as follows. Replace the original
$ lmf noiactiv cu vnk=8 vbigbas=t vpwmode=11 voveps=0d7 band:fn=syml
with:
$ lmf noiactiv cu vnk=8 vbigbas=t vpwmode=11 voveps=0d7 vrot=t rs=101 'band~rot=(1,1,0)pi/2~fn=syml'
 –rs=101 tells the charge density reader to rotate the local densites (the density was generated in the unrotated coordinate system).
 –band~rot= is necessary because lmf will not automatically rotate the kpoints read from the syml.ext.
Run a modifed band pass calculation and compare bnds.cu with bnds.cupwmode11. You should see that the kpoints are different, but that the bands are essentially identical. (There are slight differences relating to the numerical instabilities in the overlap originating from the addition of APW’s.)
This shows that the bands are replicated in the rotated coordinate system.
Finally, modify syml.cu by uncommenting the first line so it reads:
% map kz=(q^2+.01^2qx^2qy^2)^.5*(qz>0?1:1)
and repeat the lmf band pass. You should see that k_{x} and k_{y} are unchanged, but k_{z} is slightly modified. Similarly the bands are slightly modified.
The basp file
File basp.ext contains information about the lmf basis set. In the Bi_{2}Te_{3} tutorial it reads:
BASIS:
Te RSMH= 1.615 1.681 1.914 1.914 EH= 0.888 0.288 0.1 0.1 P= 5.901 5.853 5.419 4.187
Bi RSMH= 1.674 1.867 1.904 1.904 EH= 0.842 0.21 0.1 0.1 P= 6.896 6.817 6.267 5.199 5.089 PZ= 0 0 15.936
The file consists of one line for each species (it is not an error if a species is missing). The line begins with the species name, optionally followed by
 envelope shape parameters RSMH=… and EH=… and possibly RSMH2=… and EH2=…
 augmentation sphere boundary conditions P=…
 Local orbital information PZ=….
I/O is performed by routine iobzwt in subs/ioorbp.f.
The wkp file
wkp.ext keeps Fermi level efermi and band weights wtkb(nevx,nsp,nq) for Brillouin zone integration.
This binary file consists of a header in a single record, followed by second record containing wtkb(nevx,nsp,nq).
The header contains a dimensioning parameter, number of spins and irreducible k points in the Brillouin zone:
nevx nq nsp efermi
I/O is performed by routine iobzwt in subs/suzbi.f.
The save file
save.ext keeps a log of summary information for each iteration in iterations to selfconsistency.
Each line records data for one iteration, including algebraic variables declared on the command line, followed by variables kept in the ctrl file by the % save directive, system magnetic moment (in magnetic systems) and total energy.
The box below shows an example from the basis set tutorial:
h gmax=4.4 nkabc=3 ehf=126808.3137885 ehk=126808.2492178
i gmax=4.4 nkabc=3 ehf=126808.3039837 ehk=126808.2781451
i gmax=4.4 nkabc=3 ehf=126808.2952016 ehk=126808.2925665
...
c gmax=4.4 nkabc=3 ehf=126808.2950696 ehk=126808.2950608
i gmax=4.4 nkabc=3 ehf=126808.2950731 ehk=126808.2950686
i gmax=6 nkabc=3 ehf=126808.294891 ehk=126808.294886
The character at the beginning of the line has the following significance:
 c selfconsistency achieved within the specified tolerances
 i intermediate iteration, not selfconsistent
 h the first iteration
 x the maximum number of iterations was reached without achieving convergence
 C (molecular statics) when both charge density is converged and forces fall below specified tolerance
File I/O is performed by subs/iosave.f.
The spf file
File spf.ext, and sitespecific files spfn.ext contain spectral functions along symmetry lines generated by lmgf, with the band switch.
How to make spf.ext is explained in this document. It contains a 1line header consisting of values for qcut to be explained below, e.g.
# 1.19592 1.19592 2.19592 2.90302 3.61013
The header is followed by a sequence of lines:
[ w qq0 A(up) A(dn) ( this line is not present in the file)]
1.00000 0.00000 0.004900 0.004423
1.00000 0.01040 0.004896 0.004420
1.00000 0.02080 0.004886 0.004411
...
1.00000 3.61013 0.001589 0.001327
0.99800 0.00000 0.005079 0.004586
0.99800 0.01040 0.005075 0.004583
...
Notes:
 A is the spectral function.
 The frequency is ω = E−E_{F}.
 The second column is the distance from the first qpoint of the first symmetry line i.e. the position in a band figure relative to the left edge. A panel begins/ends where points coincide with qcut.
 Bash script SpectralFunction.sh will generate figures directly from spf.ext.
Routine iospf in gf/specfun.f reads and writes spf.ext.
Example: qcut shown above was generated from the following symmetry lines file:
116 0 0 0 0 0 1.195917 Gamma to H
97 1 0 0 0 0 0 M to Gamma
68 0 0 0 .5 .5 0 Gamma to X
68 .5 .5 0 1 0 0 X to M
The dos file
This file contains one or more densitiesofstates on a uniform mesh of energy points. The traditional (standard) format for dos.ext is described here.
Note: dos.ext may alternatively be written in standard Questaal format for 2D arrays (if generated using, e.g. dos@rdm).
The traditional format begins with a header line
1.00000 0.00000 501 16 1 0.01843 0.00000 1 ↑ ↑ ↑ ↑ ↑ ↑ ↑ ↑ emin emax ne nchan nsp ef delta fmt
 emin First energy point on mesh
 emax Last energy point on mesh
 ne Number of points
 nchan Number of DOS per spin
 nsp Number of spins
 ef Fermi level
 delta Sampling broadening
 fmt Formatting style; should be 1.
Next follow the DOS (ne points per channel) written as nsp×nchan separate records.
The smpot0 file
File smpot0.ext contains a reference potential and density for certain Fourier components of the mesh potential (density) in reciprocal space. This file is used by lmf in conjuction with the application of an external potential, invoked with the vext switch.
The Fourier components retained correspond to the nonzero Fourier components in the external potential. The file has a simple structure, with the standard Questaal format.
% rows [number of rows]
1 v_k rho_k
2 v_k rho_k
...
v_k and rho_k are the (complex) Fourier coefficients to the reference potential.
The socscl file
File socscl.ext enables you to scale the spinorbit coupling matrix element by site. It is used by lmgf and lmpg. You must create this file, in the standard Questaal format It should contain as many lines as there are sites.
Example Supposing there are 4 sites and you want to scale L·S in the last two sites only, by a parameter soscl which you control from the command line. Create socscl.ext as follows:
% const soscl=1
1
1
{soscl}
{soscl}
lmgf vsoscl=.5 ...
Selected files generated by lmf or lm for optics
File jdos
jdos.ext is generated by lmf or lm when making single or joint DOS when using the optics package (OPTICS_MODE<0)
File is written in standard Questaal format. Data is written up to four columns as shown in the box below.
Energy  totalDOS  Mull1  Mull2 
See this tutorial for an example.
The opt file
When lm or lmf is run in optics mode (OPTICS_MODE>0) it generates the imaginary part of the dielectric function.
File opt.ext is written in standard Questaal format for the longitudinal components of ε as a function of frequency, as shown in the box below.
ω  ε_{x}  ε_{y}  ε_{z} 
If the calculation is spin polarized, ε is resolved by spin and three additional columns are written. The resolution by spin is not physically observable, but the code resolves it anyway to enable you to distinguish the up and down contributions to ε. For the physically observable ε, combine spinup and spindown columns.
Files optdata and optdatac
These files contain matrix elements of the velocity operator. optdata.ext is written when –opt:write appears on the commandline; optdatac.ext is written when –opt:woptmc appears.
optdata.ext contains matrix elements of the square of the velocity operator, symmetrized over kpoints, while optdatac.ext contains matrix elements of the velocity operator itself. It is not symmetrized.
Both files are written in binary format. The first two records are common to both files.
1.  Efermi  ndham  nsp  nkp 
2.  evals(1:ndham,1:nsp,1:nkp) 
The remaining records depend on the type of file :
3. (optdata)  nfilm  nempm  nspx  nkp 
4. (optdata)  optmt(1:3,nfilo:nfiup,nemlo:nemup,nspx,nkp) 
3. (optdatac)  nfilo  nfiup  nemlo  nemup  nspx  nkp  qp 
4. (optdatac)  optmt(1:3,nfilo:nfiup,nemlo:nemup,nspx,nkp)  
5. (optdatac)  optmc(1:3,nfilo:nfiup,nemlo:nemup,nspx,nkp) 
 nfilo, nfiup = indices to first and last bands in the “occupied channel” for which matrix elements are stored
 nfilm = nfiup−nfilo
 nemlo, nemup = indices to first and last bands in the “unoccupied channel” for which matrix elements are stored
 nempm = nemup−nemlo
 nspx = number of independent spins (1 in nonmagnetic or noncollinear cases, two otherwise)
 nkp = number of kpoints
 qp(3,nkp) = vector of nkp kpoints
Selected files generated by lmgf or lmpg
The vshft file
File vshft.ext holds information about potential shifts used by lmgf and lmpg.
In these codes the Fermi level E_{F} is usually fixed and a potential shift vconst is added to make the system charge neutral for E_{F}.
The first line contains information about these parameters. In lmgf has a single value for vconst, e.g.
ef=0.0850000 vconst=0.0518662
while lmpg has three, e.g.
ef=0.0000000 vconst=0.1035472 vconst(L)=0.0867085 vconst(R)=0.2418164
You can optionally add sitedependent potential shifts. After the first line, add a line site shifts followed by as many lines as desired, one line per site shift, e.g.:
ef=.03 vconst=.01 vconst(L)=.02 vconst(R)=.03
site shifts
3 .1
4 .2
Files lbc and rbc
These files are generated by lmpg. They are binary files containing information about the left and right surface Green’s function used to embed the active region
Files jz,jzk and rzl,rzr
These files are generated by lmpg. They are written in the standard Questaal format and contain information about the kintegrated (jz.ext), and kresolved (jz.ext) transmission probability , and left and right reflection probablities (rzl.ext and rzr.ext).
Selected files generated by the GW codes
The GW codes operate through a shell script. The final step is carried out by hqpe, which assembles output generated by other executables in the GW code to assemble files suitable for reading.
In the oneshot case, the most useful file is the QPU file. In the QSGW case, it is sigm.ext which contains the quasiparticlized selfenergy in a form lmf can read and add to the LDA potential.
QPU
QPU (and in the spin polarized case QPD) contain the main results of a GW calculation in an easytoread format. An example of this file for a oneshot calculation is shown below. In the QSGW case, the file is slightly different; for example there is no Z factor.
E_shift= 0.1135090155598752D+01 0.1902823497322418D+01 0.2111434832164544D+01 eV
q state SEx SExcore SEc vxc dSE dSEnoZ eLDA eQP eQPnoZ eHF Z FWHM=2Z*Simg ReS(elda)
0.00000 0.00000 0.00000 4 14.80 1.95 3.07 13.59 0.07 0.09 1.45 2.28 2.51 3.47 0.79 0.00000 13.68005
0.00000 0.00000 0.00000 5 4.82 1.40 4.58 11.77 0.75 0.97 1.10 1.09 1.09 7.78 0.78 0.02563 10.80323
0.50000 0.50000 0.50000 4 14.63 1.91 3.15 13.28 0.09 0.12 2.64 3.50 3.73 4.77 0.77 0.00000 13.39330
0.50000 0.50000 0.50000 5 4.99 2.15 4.54 12.66 0.77 0.98 0.00 0.00 0.00 6.65 0.79 0.00000 11.68493
0.00000 0.00000 1.00000 4 14.39 1.69 3.41 12.58 0.07 0.09 4.30 5.14 5.37 6.67 0.77 0.09531 12.66525
0.00000 0.00000 1.00000 5 4.20 0.92 4.24 10.31 0.77 0.96 0.82 0.82 0.84 5.51 0.81 0.00000 9.35651
The first line contains three energy shifts eLDA, eQP and eQPnoZ that are needed to set a particular state n (e.g. a valence band maximum) to zero. In the Table above, this was state 5 at the second kpoint. These shifts are determined by hqpe. You can control how they are set by running lmgw with insul=n.
The columns have the following meaning, and define eLDA, eQP, and eQPnoZ:
 q : k point.
 state : Band index n, with n=1 corresponding to lowest eigenvalue.
 SEx : $\langle \Psi_{\mathbf{q}n}  \Sigma_\mathrm{x}  \Psi_{\mathbf{q}n}\rangle$ where ${\Sigma_\mathrm{x}}$ is the exchange potential computed from valence + core2 levels.
The division of core levels into core1 and core2 is desribed in Section IIB of Phys. Rev. B76, 165106 (2007).  SExcore : $\langle \Psi_{\mathbf{q}n}  \Sigma_\mathrm{x}  \Psi_{\mathbf{q}n}\rangle$ where ${\Sigma_\mathrm{x}}$ is computed from core1 levels.
 SEc : $\langle \Psi_{\mathbf{q}n}  \Sigma_{c}(\epsilon_{\mathbf{q}n})  \Psi_{\mathbf{q}n}\rangle$ where ${\Sigma_{c}}$ is the correlation selfenergy computed from valence + core2 levels.
 vxc : LDA exchange correlation energy $\langle \Psi_{\mathbf{q}n} \mid V_\mathrm{xc}^\mathrm{LDA}[n^\mathrm{tot}] \mid \Psi_{\mathbf{q}n}\rangle$ generated by lmf, used to subtract from the GW selfenergy to get QP shifts.
Note: If you carry out a 1shot calculation with the QSGW as a starting point (lmgw vxcsig), vxc is the QSGW self energy.  dSE : QP shift relative to LDA including a Z factor, $Z_{\mathbf{q}n} \times \mathrm{dSEnoZ}$.
 dSEnoZ : QP shift relative to LDA without a Z factor : $\langle \Psi_{\mathbf{q}n} \mid \Sigma_\mathrm{x}^\mathrm{core1} + \Sigma^\mathrm{val+core2}_{xc}(\epsilon_{\mathbf{q}n})  V_\mathrm{xc}^\mathrm{LDA}[n^\mathrm{tot}] \mid \Psi_{\mathbf{q}n}\rangle$ .
 eLDA : LDA eigenvalues $\epsilon^\mathrm{LDA}_{\mathbf{q}n}$, generated by lmf.
Note: If you carry out a 1shot calculation with the QSGW as a starting point, eLDA is the the QSGW level generated by lmf.  eQP : QP level with shift computed including the Z factor, $\epsilon^\mathrm{LDA}_{\mathbf{q}n} + \mathrm{dSE}$.
 eQPnoZ : QP level with shift computed omitting the Z factor, $\epsilon^\mathrm{LDA}_{\mathbf{q}n} + \mathrm{dSEnoZ}$.
 eHF : Hartree Fock energy $\epsilon^\mathrm{LDA}_{\mathbf{q}n} + \mathrm{SEx} + \mathrm{SExcore}  \mathrm{vxc}$.
 Z : Z factor, $Z_{\mathbf{q}n}=(1\partial \Sigma_\mathrm{c}^\mathrm{core2+valence}(\epsilon)/\partial\epsilon)^{1}$ evaluated at $\epsilon_{\mathbf{q}n}$.
 FWHM : $2 Z_{\mathbf{q}n} \times \mathrm{Im} \langle\Psi_{\mathbf{q}n}\mid \Sigma_\mathrm{c}^\mathrm{core2+valence}(\epsilon_{\mathbf{q}n})\mid\Psi_{\mathbf{q}n}\rangle$. This quantity is related to the quasiparticle lifetime.
 ReS(elda) : $\mathrm{Re}\, \langle\Psi_{\mathbf{q}n}\mid \Sigma_\mathrm{x}^\mathrm{core1} + \Sigma_\mathrm{xc}^\mathrm{core2+valence}(\epsilon_{\mathbf{q}n}) \mid \Psi_{\mathbf{q}n}\rangle$
TOTE.UP and TOTE2.UP
These files (and TOTE.DN, TOTE2.DN in the spin polarized case) contain a portion of the information in QPU file, but with more decimal places of precision.
TOTE.UP contains LDA and quasiparticle energies. These values are relative to a Fermi energy determined by the a Gaussian sampling integration. It begins with a header line
3 2 0.2830887881465354D+01 0.1135090155598752D+01 0.1902823497322418D+01 0.2111434832164544D+01
which indicates how many kpoints and states at each point are in the file, the Fermi energy, as determined by Gaussian sampling, followed by the same energy shifts for eLDA, eQP, eQPnoZ found in the QPU header. The remaining lines contain same information denoted by columns eLDA, eQP, eQPnoZ, Z in the QPU file.
TOTE.UP is similar, but the header contains no shifts; the band levels are the same as in TOTE2.UP but without the addiitional shifts. Thus these energies are relative the Fermi level printed in the header. Note: TOTE.UP contains the Fermi level in Ry, not eV, even though the energies in the body of the file are in eV.
Selected files read or generated by lmfgws
The se file
The se file contains the frequencydependent selfenergy generated by the GW code. It is generated by spectral from raw GW output files SEComg.UP (and SEComg.DN in the magnetic case), for use by lmfgws. spectral writes to file se; it must be renamed to se.ext for lmfgws to read it.
The file contains a header and a body; what is inthe latter is specified by filecontents given in the header. The file can be in either ASCII for binary format.
Records are as follows:
 header, 3 records
 0 versionnumber filecontents units
The first element (0) is a placeholder for future use.
This documentation is written for versionnumber=4.
1s digit filecontents governs how Σ(ω) is written in Step 7
0 : sigm(1:nw,1:nband,1:nq,1:nsp), single record
1 : sigm(1:nw,1:nband,iq,isp), sequence of nkp*nsp records
2 : sigm is written in a userspecified format – usually sigm(1:nw,1:nband)
10s digit filecontents governs what frequencyindependent selfenergies are stored
Add 1 : QSGW Σ^{0} is stored
Add 2 : Exchange selfenergy is stored
Add 4 : LDA XC potential is stored.
100s digit filecontents governs what frequencydependent object is stored
0 : diagonal parts of selfenergy (complex)
1 : spectral function (real)  [for real frequencies] : nsp nband nqp nw ommin ommax mu (Real axis flagged by nw>0)
[for Matsubara frequencies] : nsp nband nqp −nw beta mu (Imaginary axis flagged by nw<0)
Number of spins, bands, kpoints and frequencies; first and last frequency; chemical potential (nw>0)
Number of spins, bands, kpoints and (negative of number of) frequencies; inverse temperature; chemical potential (nw<0)  list of bands entering into spectral function, using Questaal standard syntax for integer lists.
If 0, bands comprise 1…nband
 0 versionnumber filecontents units
 kpoints qp(3,nqp), written as a single record.
 quasiparticle levels eig(nband,nqp,nsp), written as a single record. Note: these levels are saved relative to the chemical potential.
 QP Σ^{0} = sigm(nband,nqp,nsp), in one record (written if 10s digit filecontents contains 1)
 Fock exchange Σ_{x} = sex(nband,nqp,nsp), in one record (written if 10s digit filecontents contains 2)
 LDA exchangecorrelation V_{xc} = vxc(nband,nqp,nsp), in one record (written if 10s digit filecontents contains 4)
 If 100s digit filecontents = 0 : $\omega$dependent selfenergy $\Sigma(\mathbf{k},\omega)$ = sigm(1:nw,1:nband,1:nq)
If 100s digit filecontents = 1 : $\omega$dependent spectral function $A(\mathbf{k},\omega)$
$\Sigma$ or $A$ is written in one or multiple records, depend on 1s digit filecontents.
See this tutorial for an instance where this file is written and read.
Routine subs/ioseh.f performs the I/O.
Files sdos, seia, pes, pesqp, spq, seq
These files are generated by lmfgws. All files are written in standard Questaal format. There are also files sdos2.ext etc corresponding to the second spin.
For a test that makes and checks many of these files, do
$ gwd/test/test.gwd fe 4 5
 File sdos.ext (sdos2.ext)
 Densityofstates, i.e. k integrated spectral functions. Columns are: $\omega ~ A(\omega) ~ A_0(\omega)$.
 File seia.ext (seia2.ext)
 Spectral function at a specific qpoint. The header describes each column. Note that $\Sigma(\mathbf{k},\omega)$ is not the true selfenergy. It is $\overline{\Sigma(\mathbf{k},\omega)} = \Sigma(\mathbf{k},\omega)  \Sigma^0(\mathbf{k},\omega)$ the last is subtracted so that $\overline{\Sigma(\mathbf{k},\omega)} = 0$ at the QP level.
 File pes.ext (pes2.ext)
 Simulation of photoemission spectra.
 File pesqp.ext (pesqp2.ext)
 Simulation of photoemission spectra from noninteracting $A^0(\omega)$. Works with SO coupling.
 File spq.ext
 Contains the Spectral function in the form of an se file. lmdmft will generates this file on a mesh, to enable further processing e.g. plbnds can make an “interacting band” plot of the spectral function.
 File seq.ext
 Contains the selfenergy in the form of an se file. lmdmft will generates this file on a mesh, to enable further processing.
Selected files read or generated by lmfdmft
lmfdmft requires an independent input file to make an interface to a CTQMC solver. For the Haule solver, this is indmfl.ext. A file sig.inp containing the DMFT selfenergy in the correlated subspace. This is generated by the CTQMC solver, but a template must be created. lmfdmft will do this automatically. Other files lmfdmft generates as a regular part of the DMFT cycle are the hybridization function delta.ext, and for the Haule code eimp1.ext All of these files are described here.
Additionally lmfdmft can create for different purposes a projection of the Green’s function $G_{\mathrm{loc}}$ into the correlated subspace, either k integrated (gloc.ext) or k resolved (gkloc.ext) or the interacting, k resolved G, not projected onto a subspace.
Files sig.inp, gloc.ext, and gkloc.ext
sig.inp, gloc.ext, and gkloc.ext all have similar formats. There may be a header line supplying additional information. Next follow one line for each frequency, which contains (e.g. for sig.inp)
freq Re Sig1 Im Sig1 Re Sig2 Im Sig2
for as many channels as exist in the subspace. For the CTQMC solver freq is understood to be an imaginary number.
gloc.ext, and gkloc.ext are created with the switch –gprt.
File gk.ext
When G is written in the basis of eigenfunctions (–gprt~mode=8), it is written as a binary file into gk.ext, owing to its large size.
The records are written as follows:
1.  ndham  nomg  nkfbz  n123  lsigim  
2.  omega(1:nomg)  
cycled for each frequency and k point:  
1.  iomg  nlo  nhi  iqfbz  iq  iv  qpr 
2.  G(nlo:nhi,nlo:nhi) 
The first pair records are written only once:
 Dimensioning parameters
 ndham rank of 1body hamiltonian
 nomg number of frequencies written
 nkfbz Total number of k points
 n123 No. divisions for the 3 reciprocal lattice vectors into microcells
 lsigim 0 or 1 depending on whether frequencies are real or imaginary
 omega contains the vector of nomg frequencies.
The next pair of records are written for each frequency (1:nomg) and k point (1:nkfbz).
 Indexing and k point information:
 iomg = frequency index
 nlo,nhi = first and last eigenstate written for this G
 iqfbz = k point index
 iq = irreducible k point indexfrom which this point was generated
 iv = triplet of indices i_{1},i_{2},i_{3}, to microcell in the full Brillouin zone
 qpr = k point in units of 2π/a
 G in the basis of 1particle eigenstates
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