The type
fortrandouble
allows to use the letters
"eEdDqQ"
for exponent operators. This alters in what precision the number is parsed.

This web page lists all elements and attributes that can be used in the input file of an exciting calculation:

  • elements are defined according to the general XML conventions. Example: The element groundstate is used to set up a self-consistent calculation of the ground-state energy.
  • attributes are defined according to the general XML conventions. An attribute is always connected to an element. In exciting an attribute generally specifies a parameter or a set of parameters which are connected to the corresponding element. Example: The attribute xctype of the element groundstate defines which exchange-correlation potential is used in the self-consistent calculation.
  • The input file of an exciting calculation is named input.xml. It must be a valid XML file, and it must contain the root element input.

    Unless explicitly stated otherwise, exciting uses atomic units (\hbar = m_{e} = e = 1):

  • Energies are given in Hartree:

    1 Ha = 2 Ry = 27.21138386(68) eV = 4.35926 10^{-18}\ J

  • Lengths are given in Bohr:

    1 a_{\rm Bohr}\ = 0.52917720859(36) {\buildrel _{\circ} \over {\mathrm{A}}} \ = 0.52917720859(36) 10^{-10} \ m

  • Magnetic fields are given in units of

    1 a.u. = \displaystyle\frac{e}{a_{\rm Bohr}^2}\ = 1717.2445320376\ Tesla.

  • Note: The electron charge is positive, so that the atomic numbers Z are negative.

    \<exciting>exciting</exciting> input reference input
    A vector is a space separated list of floating point numbers.

    Example:

     "1.3 2.3e4 3 90"

    List of space separated integers. Three dimensional vector as three space separated floating point numbers. Three dimensional vector as three space separated floating point numbers. Space separated list of three integers.

    Example:

      "1 2 3"
      

    Space separated list of two integers

    Example:

     "1 2" 

    A prefix to be prepended to the output files. nonreplace Decides if the ground state is calculated starting from scratch, using the densities from file or if it is skipped and only its associated input parameters are read in. Also applies fo structural optimization run. If the IBS correction to the force should be calculated Because calculation of the incomplete basis set (IBS) correction to the force is fairly time-consuming, it can be switched off by setting
     tfibs 
    to
     "false"
    This correction can then be included only when necessary, i.e. when the atoms are close to equilibrium in a structural relaxation run.
    The attribute is set to
     "true"
    if the force should be calculated at the end of the self-consistent cycle This variable is automatically set to
     "true"
    when performing structural optimization.
    When set to
    "true"
    only symmorphic space-group operations are to be considered, i.e. only symmetries without non-primitive translations are used anywhere in the code.
    This is the scissors shift applied to states above the Fermi energy. Affects DOS, optics and band structure plots. if
    "true"
    , a fast method to calculate APW-lo, lo-APW and lo-lo parts of the momentum matrix elements in the muffin-tin is used.
    The intraband attribute is
    "true"
    if the intraband term is to be added to the optical matrix (q=0)
    Select to include or exclude states Select for initial or final state range The element plot1d specifies sample points along a path. The coordinate space (lattice or cartesian)is chosen in the context of the parent. A path consists of at least two points and a number of divisions. Defines a 2d plot domain. Defines a 3d plot domain. The element
    pointstatepair
    defines a { \bf k} -point and state index pair.
    The kstlist element is used in the LSJ and wavefunction plot element This is a user-defined list of { \bf k} -point and state index pairs which are those used for plotting wavefunctions and writing { \bf L} , { \bf S} and { \bf J} expectation values. The xml element
     input
    is the root element of the exciting input file. It must contain one element
    structure 
    and the element
    groundstate 
    .

    Find a minimal input file instance described here.

    Title of the input file. The structure element contains all structural information such as unit cell and atom positions. This element is used by the spacegroup tool to generate structures and supercells The symmetries element is output from the spacegroup program the values are currently not used in the exciting program The lattice element defines lattice from a,b,c, and angles. noreplace noreplace noreplace Number of repeated cells in each direction. Herman Mauguin symbol giving the spacegroup hrmg Defines the unit cell of the crystal via the 3 basis vectors. The unit cell is spanned by 3 base vectors that define the lattice coordinates. Defines one basis vector in Cartesian coordinates. avec Scales all the lattice vectors by the same factor. This is useful for varying the volume. scale Allows for an individual scaling of each lattice vector separately.
    "1 1 1"
    means no scaling.
    (sc1|sc2|sc3)
    Defines the atomic species, i.e. the chemical element. The atomic coordinates and, optionally, quantities relevant for magnetic calculations are defined in the subelement(s) atom. Defines the position and other attributes of one atom in the unit cell. noname Position in lattice coordinates. atposl Muffin-tin external magnetic field in Cartesian coordinates. The desired muffin-tin moment for a Fixed Spin Moment (FSM) calculation. If present defines LDA plus U parameters for species notaname notaname notaname Defines the file that contains the species definition. It is looked up in the species directory specified by the species path. By default, the name of the file is element. xml, e.g. Ag.xml. spfname Optional attribute that may be used in visualization and by converters. It is ignored by exciting spsymb Optional attribute that may be used in visualization and by converters. It is not used in exciting noreplace> Defines the muffin-tin radius; this optional parameter allows to override species file or automatic determination. The muffin-tin radius defines the region around the atomic nucleus where the wave function is expanded in terms of atomic-like functions. In contrast, the interstitial region (=region not belonging to any muffin-tin) is described by planewaves. Defines the address/URI of a species file provided in web. If this attribute is specified, all other attributes
    Gives the path to the directory containing the species files. It can be an HTTP URL too (needs
    wget
    ).
    sppath
    Has to be set to
    "true"
    if one wants to calculate an isolated molecule. If it is
    "true"
    , then the atomic positions, {\bf a} , are assumed to be in Cartesian coordinates. The lattice vectors are also set up automatically with the i-th lattice vector given by {\bf A}^i=A_i\hat{\bf e}^i, where A_i=\max_{\alpha,\beta}\left|{\bf a}^{\alpha}_i-{\bf a}^{\beta}_i\right| +d_{\rm vac} with \alpha and \beta labeling atoms, and d_{\rm vac} determines the size of the vacuum around the molecule. The last variable is set by the attribute
    vacuum
    .
    Determines the size of the vacuum around the molecule. Vectors with lengths less than this are considered zero. If
    "true"
    automatic determination of the muffin tin radii is allowed.
    Allows the primitive unit cell to be determined automatically from the conventional cell. This is done by searching for lattice vectors among all those which connect atomic sites, and using the three shortest ones which produce a unit cell with non-zero volume. Set to it to
    "true"
    if the crystal can be shifted such that the atom closest to the origin is exactly at the origin.
    The groundstate element is required for any calculation. Its attributes are the parameters and methods used to calculate the groundstate density. If the
    spin
    element is present calculation is done with spin polarization.
    spinpol
    The desired total moment for a FSM calculation. Alows to apply a constant B field This is a constant magnetic field applied throughout the entire unit cell and enters the second-variational Hamiltonian as \frac{g_e\alpha}{4}\,\vec{\sigma}\cdot{\bf B}_{\rm ext}, where g_e is the electron g -factor (2.0023193043718). This field is normally used to break spin symmetry for spin-polarised calculations and considered to be infinitesimal with no direct contribution to the total energy. In cases where the magnetic field is finite (for example when computing magnetic response) the external { \bf B} -field energy reported in
    INFO.OUT
    should be added to the total by hand. This field is applied throughout the entire unit cell. To apply magnetic fields in particular muffin-tins use the
    bfcmt
    vect ors in the
    atoms
    block. Collinear calculations are more efficient if the field is applied in the z -direction.
    If
    spinorb
    is
    "true"
    , then a \boldsymbol \sigma\cdot{ \bf L} term is added to the second-variational Hamiltonian.
    Set to
    "true"
    if a spin-spiral calculation is required. Experimental feature for the calculation of spin-spiral states. See vqlss for details.
    Is the { \bf q} -vector of the spin-spiral state in lattice coordinates. Spin-spirals arise from spinor states assumed to be of the form \Psi^{ \bf q}_{ \bf k}({ \bf r})= \left( \begin{array}{c} U^{{\bf q}\uparrow}_{ \bf k}({\bf r})e^{i({ \bf k+q/2})\cdot{ \bf r}} \\ U^{{ \bf q}\downarrow}_{\bf k}({ \bf r})e^{i({\bf k-q/2})\cdot{ \bf r}} \\ \end{array} \right). These are determined using a second-variational approach, and give rise to a magnetization density of the form {\bf m}^{ \bf q}({ \bf r})=(m_x({\bf r})\cos({ \bf q \cdot r}), m_y({\bf r})\sin({ \bf q \cdot r}),m_z({\bf r})), where m_x , m_y and m_z are lattice periodic. See also spinprl. After each iteration the external magnetic fields are multiplied with reducebf. This al- lows for a large external magnetic field at the start of the self-consistent loop to break spin symmetry, while at the end of the loop the field will be effectively zero, i.e. infinitesimal. See bfieldc and atom element. 0 1 2 3
    If preset HartreeFock calculation is triggered. Energy convergence tolerance. Optional configuration options for eigenvector solver. solvertype Selects the eigenvalue solver for the first variational equation 1 2 3 In the default calculation the matrix is sored in packed form. When using multithreaded BLAS setting this parmeter to
    "false"
    increases efficiency.
    Tolerance parameter for the ARPACK shift invert solver Error tolerance for the first-variational eigenvalues using the LAPACK Solver
    If present exact exchange calculation is triggered. (experimental) Maximum number of iterations when solving the exact exchange integral equations. The optimised effective potential is determined using an interative method. [Phys. Rev. Lett. 98, 196405 (2007)]. At the first iteration the step length is set to tauoep(1). Dur- ing subsequent iterations, the step length is scaled by tauoep(2) or tauoep(3), when the residual is increasing or decreasing, respectively. See also maxitoep. If present Reduced Density Matrix Funcional Theory calculation is triggered XC functional. maximum number of self-consistent loops. maximum number of iteration for occupation number optimization. maximum number of iteration for natural orbital optimization. step size for occupation numbers. Step size for natural orbital coefficients. exponent for the functional. temperature. Specifications on the file formats for output files. Selects the file format of the STATE file.
    nonreplace Decides if the groundstate run is skipped, calculated from scratch, or continued from the file STATE.OUT. ngridk Number of k grid points along the basis vector directions. The parameter
    rgkmax
    implicitly determines the number of basis functions and is one of the crucial parameters for the accuracy of the calculation. It represents the product of two quantities: R_{MT,\, Min}, the smallest of all muffin-tin radii, and |{ \bf G}+{ \bf k}|_{max}, the maximum length for the { \bf G}+{ \bf k}\ vectors. Because each { \bf G}+{ \bf k}\ vector represents one basis function,
    rgkmax
    gives the number of basis functions used for solving the Kohn-Sham equations. Typical values of
    rgkmax
    are between 6 and 9. However, for systems with very short bond-lengths, significantly smaller values may be sufficient. This may especially be the case for materials containing carbon, where
    rgkmax
    may be 4.5-5, or hydrogen, where even values between 3 and 4 may be sufficient. In any case, a convergence check is indispensible for a proper choice of this parameter for your system!
    If the RMS change in the effective potential and magnetic field is smaller than
    epspot
    , then the self-consistent loop is considered converged and exited. For structural optimization runs this results in the forces being calculated, the atomic positions updated and the loop restarted. See also maxscl.
    Energy convergence tolerance. Convergence tolerance for the forces during the SCF run. Parameters governing the automatic generation of the muffin-tin radii. When autormt is set to
    "true"
    , the muffin-tin radii are found automatically from the formula R_i\propto 1+\zeta|Z_i|^{1/3}, where Z_i is the atomic number of the i th species, \zeta is stored in rmtapm(1) and the value which governs the distance between the muffin-tins is stored in rmtapm(2). When rmtapm(2) =1, the closest muffin-tins will touch.
    Width of the smooth approximation to the Dirac delta function (must be greater than zero). A smooth approximation to the Dirac delta function is needed to compute the occupancies of the Kohn-Sham states. The attribute
    swidth
    determines the width of the approximate delta function.
    0 1 2 3 4
    Select method to determine the linearization energies. Species for which the muffin-tin radius will be used for calculating gkmax. Maximum length of |G| for expanding the interstitial density and potential. Defines the number of eigenstates beyond that required for charge neutrality. When running metals it is not known a priori how many states will be below the Fermi energy for each k -point. Setting
    nempty
    greater than zero allows the additional states to act as a buffer in such cases. Furthermore, magnetic calculations use the first-variational eigenstates as a basis for setting up the second-variational Hamiltonian, and thus
    nempty
    will determine the size of this basis set. Convergence with respect to this quantity should be checked.
    When set to
    "true"
    no symmetries, apart from the identity, are used anywhere in the code.
    When set to
    "true"
    only symmorphic space-group operations are to be considered, i.e. only symmetries without non-primitive translations are used anywhere in the code.
    When set to
    "true"
    the frozen core approximation is applied, i.e., the core states are fixed to the atomic states.
    Decides if the k -point set is to be determined automatically Used for the automatic determination of the k -point mesh. If
    autokpt
    is set to
    "true"
    then the mesh sizes will be determined by n_i=\lambda/|{ \bf A}_i|+1 .
    If the attribute
    reducek
    is
    "true"
    the \bf{k} -point set is reduced with the crystal symmetries.
    Because calculation of the incomplete basis set (IBS) correction to the force is fairly time- consuming, it can be switched off by setting tfibs to
    "false"
    This correction can then be included only when necessary, i.e. when the atoms are close to equilibrium in a structural relaxation run.
    Decides if the force should be calculated at the end of the self-consistent cycle. Angular momentum cut-off for the APW functions. Upper limit for te selfconsistency loop. This controls the amount of charge in the unit cell beyond that required to maintain neu-trality. It can be set positive or negative depending on whether electron or hole doping is required. Initial band energy step size The initial step length used when searching for the band energy, which is used as the APW linearization energy. This is done by first searching upwards in energy until the radial wavefunction at the muffin-tin radius is zero. This is the energy at the top of the band, denoted E_{\rm t} . A downward search is now performed from E_{\rm t} until the slope of the radial wavefunction at the muffin-tin radius is zero. This energy, E_{\rm b} , is at the bottom of the band. The band energy is taken as (E_{\rm t}+E_{\rm b})/2 . If either E_{\rm t} or E_{\rm b} cannot be found then the band energy is set to the default value. Energy tolerance for search of linearization energies. none Energy difference between linearisation and Fermi energy. Maximum allowed error in the calculated total charge beyond which a warning message will be issued. smallest occupancy for which a state will contribute to the density. select the mixing (relaxation) scheme for SCF mixtype 1 2 3 Initial value for mixing parameter. Used in linear mixing. Mixing parameter increase. Used in linear mixing. Mixing parameter decrease. Used in linear mixing. Some muffin-tin functions (such as the density) are calculated on a coarse radial mesh and then interpolated onto a fine mesh. This is done for the sake of efficiency. lradstp defines the step size in going from the fine to the coarse radial mesh. If it is too large, loss of precision may occur. lradstp Smallest occupancy for which a state will contribute to the density. Type of exchange-correlation functional to be used
  • No exchange-correlation funtional ( E_{\rm xc}\equiv 0 )
  • LDA, Perdew-Zunger/Ceperley-Alder, Phys. Rev. B 23 , 5048 (1981)
  • LSDA, Perdew-Wang/Ceperley-Alder, Phys. Rev. B 45 , 13244 (1992)
  • LDA, X-alpha approximation, J. C. Slater, Phys. Rev. 81 , 385 (1951)
  • LSDA, von Barth-Hedin, J. Phys. C 5 , 1629 (1972)
  • GGA, Perdew-Burke-Ernzerhof, Phys. Rev. Lett. 77 , 3865 (1996)
  • GGA, Revised PBE, Zhang-Yang, Phys. Rev. Lett. 80 , 890 (1998)
  • GGA, PBEsol, arXiv:0707.2088v1 (2007)
  • GGA, Wu-Cohen exchange (WC06) with PBE correlation, Phys. Rev. B 73 , 235116 (2006)
  • GGA, Armiento-Mattsson (AM05) spin-unpolarised functional, Phys. Rev. B 72 , 085108 (2005)
  • 2 3 4 5 20 21 22 26 30 -2 1
    Type of LDA+U method to be used. 0 1 2 3 Angular momentum cut-off for the muffin-tin density and potential. Fraction of the muffin-tin radius up to which lmaxinr is used as the angular momentum cut-off. Close to the nucleus, the density and potential is almost spherical and therefore the spherical harmonic expansion can be truncated a low angular momentum. See also fracinr. Angular momentum cut-off for the outer-most loop in the hamiltonian and overlap matrix setup. The k-point offset vector in lattice coordinates. oOrder of polynomial for pseudocharge density. Damping coefficient for characteristic function. When set to
    "true"
    , source fields are projected out of the exchange-correlation magnetic field. experimental feature.
    The attribute tevecsv is
    "true"
    if second-variational eigenvectors are calculated.
    Normally, the density and potentials are written to the file STATE.OUT only after com- pletion of the self-consistent loop. By setting nwrite to a positive integer the file will be written during the loop every nwrite iterations. The attrubute ptnucl is
    "true"
    if the nuclei are to be treated as point charges, if
    "false"
    the nuclei have a finite spherical distribution.
    The structure optimization element triggers if present a geometry relaxation. Structural optimization run. Atomic positions written to geometry.xml. Convergence tolerance for the forces during a structural optimization run. The step size to be used for structural optimization

    The position of atom \alpha is updated on step m of a structural optimization run using {\bf r}_{\alpha}^{m+1}={\bf r}_{\alpha}^m+\tau_{\alpha}^m \left({ \bf F}_{\alpha}^m+{ \bf F}_{\alpha}^{m-1}\right), where \tau_{\alpha} is set to

    tau0atm
    for m=0 , and incremented by the same amount if the atom is moving in the same direction between steps. If the direction changes then \tau_{\alpha} is reset to
    tau0atm
    .
    Resumption of structural optimization run using density in
    STATE.OUT
    but with positions from
    input.xml
    .
    Properties listed in this element can be calculated from the groundstate. It works also from a saved state from a previous run. If present a banstructure is calculated. Create a bandstructure. Must contain plot1d element for bandstructure path. Value to shift bandgap. Band structure plot which includes angular momentum characters for every atom. Wavefunction plot. Plot the wave function at a set of kpoints List of kpoints of which the wave functions should be plotted. If present a DOS calculation is started.

    DOS and optics plots require integrals of the kind g(\omega_i)=\frac{\Omega}{(2\pi)^3}\int_{\rm BZ} f({ \bf k}) \delta(\omega_i-e({\bf k}))d{ \bf k}. These are calculated by first interpolating the functions e({ \bf k}) and f({ \bf k}) with the trilinear method on a much finer mesh whose size is determined by

    ngrdos
    . Then the \omega -dependent histogram of the integrand is accumulated over the fine mesh. If the output function is noisy then either
    ngrdos
    should be increased or
    nwdos
    decreased. Alternatively, the output function can be artificially smoothed up to a level given by
    nsmdos
    . This is the number of successive 3-point averages to be applied to the function g .
    Spin-quantization axis in Cartesian coordinates used when plotting the spin-resolved DOS (z-axis by default). When lmirep is set to
    "true"
    , the spherical harmonic basis is transformed into one in which the site symmetries are block diagonal. Band characters determined from the density matrix expressed in this basis correspond to irreducible representations, and allow the partial DOS to be resolved into physically relevant contributions, for example eg and t2g.
    Number of frequency/energy points in the DOS Effective k-point mesh size to be used for Brillouin zone integration. Level of smoothing applied to DOS/optics output integer 0. Frequency/energy window for the DOS or optics plot. wdos
    Output L, S and J expectation values. List of { \bf k} -point and state pairs. Referenced by their index. Compute the effective mass tensor at the k -point given by vklem. The size of the k-vector displacement used when calculating numerical derivatives for the effective mass tensor. The number of k-vector displacements in each direction around vklem when computing the numerical derivatives for the effective mass tensor. The k-point in lattice coordinates at which to compute the effective mass tensors. Plot the charge density Exchange-correlation and Coulomb potential plots. Electron localization function (ELF). Plot of magnetization vector field. Plot of exchange-correlation magnetic vector field. Writes the electric field to file. Plot of he gradient of the magnetic vector field. Writes Fermi surface data to file. Number of states to be included in the Fermi surface plot file. Calculation of electric field gradient (EFG), contact charge. Matrix elements of the momentum operator (legacy version, required by dielectric-element). noname apply generalised DFT correction of L. Fritsche and Y. M. Gu, Phys. Rev. B 48, 4250 (1993) Linear optical response (without local field effects, legacy version). noname The components of the first- or second-order optical tensor to be calculated. The intraband attribute is
    "true"
    if the intraband term is to be added to the optical matrix (q=0)
    apply generalised DFT correction of L. Fritsche and Y. M. Gu, Phys. Rev. B 48, 4250 (1993)
    Gives the q-vector in lattice coordinates for calculating ELNES. Coulomb pseudopotential, μ*, used in the McMillan-Allen-Dynes equation.
    Phonon frequencies and eigen vectors for an arbitrary q-point. The phonon element must contain one or more q-point elements. Phonon density of states. Phonon dispersion plot. nonreplace Decides if the phonon calculation is skipped or recalculated or continued from file. ngridq Number of q grid points along the basis vector directions. The attribute
    reduceq
    is set to
    "true"
    if the q -point set is to be reduced with the crystal symmetries.
    Phonon calculations are performed by constructing a supercell corresponding to a particular {\bf q} -vector and making a small periodic displacement of the atoms. The magnitude of this displacement is given by deltaph. This should not be made too large, as anharmonic terms could then become significant, neither should it be too small as this can introduce numerical error.
    If this element is present with valid configuration, the macroscopic dielectric function and related spectroscopic quantities in the linear regime are calculated through either time-dependent DFT (TDDFT) or the Bethe-Salpeter equation (BSE). The intraband attribute is
    "true"
    if the intraband term is to be added to the optical matrix (q=0)
    Is
    "true"
    if to consider the time-ordered version of the dielectric function
    Is
    "true"
    if to consider the time-ordered version of xc kernel (MBPT derived kernels only)
    Is
    "true"
    if to consider the anti-resonant part for the dielectric function
    Is
    "true"
    if to consider the anti-resonant part for the MBPT derived xc-kernels
    Split parameter for degeneracy in energy differences of MBPT derived xc kernels true if analytic continuation from the imaginary axis to the real axis is to be performed number of energy intervals (on imaginary axis) for analytic continuation
    "true"
    if Lindhard like function is calculated (trivial matrix elements)
    "true"
    if only diagonal part of xc-kernel is used
    angular momentum cutoff for Rayleigh expansion of exponential factor for ALDA-kernel alpha-parameter for the static long range contribution (LRC) model xc kernel alpha-parameter for the dynamical long range contribution (LRC) model xc kernel beta-parameter for the dynamical long range contribution (LRC) model xc kernel treatment of macroscopic dielectric function for {\bf Q} -point outside of Brillouin zone. A value of 0 uses the full {\bf Q} and and the ({\bf 0},{\bf 0}) component of the microscopic dielectric matrix is used. A value of 1 invokes a decomposition {\bf Q}={\bf q}+{\bf G}_{\bf q} and and the ({\bf Q}_{\bf q},{\bf Q}_{\bf q}) component of the microscopic dielectric matrix is used. defines which xc kernel is to be used 0 1 2 3 4 5 7 8
    "true"
    if the TDDFT calculation is to be resumed starting from a new xc kernel.
    nonreplace nosymscr nosym is
    "true"
    if no symmetry information should be used for screening
    ngridkscr k-point grid sizes for screening reducekscr reducek is
    "true"
    if k-points are to be reduced (with crystal symmetries) for screening.
    vkloffscr k-point offset for screening rgkmaxscr smallest muffin-tin radius times gkmax for screening nemptyscr number of empty states defines which screening is used
    nosymbse set to
    "true"
    if no symmetry information should be used for BSE.
    reducekbse reducek is
    "true"
    if k-points are to be reduced (with crystal symmetries) for BSE.
    vkloffbse k-point offset for BSE rgkmaxbse smallest muffin-tin radius times gkmax Method of how an almost Hermitian matrix is inverted. A value of 0: invert full matrix (matrix is allowed to be not strictly Hermitian); a value of 1: take the Hermitian average for inversion; a value of 2: assume Hermitian and use the upper triangle; a value of 3: assume Hermitian and use the lower triangle. true if q-point set is taken from first Brillouin zone defines how the screened Coulomb interaction matrix is to be averaged (important for the singular terms)
    "true"
    if the body of the screened Coulomb interaction is to be averaged (q=0)
    "true"
    if the head of the screened Coulomb interaction is to be averaged (q!=0)
    "true"
    if the wings of the screened Coulomb interaction is to be averaged (q!=0)
    "true"
    if the body of the screened Coulomb interaction is to be averaged (q!=0)
    true if effective singular part of direct term of BSE Hamiltonian is to be used angular momentum cutoff of the spherical harmonics expansion of the dielectric matrix number of points used for the Lebedev-Laikov grids (must be selected according to Ref.LebLaik) maximum number of excitons to be considered in a BSE calculation nbfbse,nafbse number of states below and above the Fermi level nbfce,nafce defines which parts of the BSE Hamiltonian are to be considered
    Describe transitions between Kohn-Sham states for the calculation of the Kohn-Sham response function (and screening) here. Individual transitions can be defined as well as a range (or a list) of initial and final states can be defined. A list of individual transitions consisting of an initial state a final state and a k-point is given here. An empty list amounts to no transitions at all. An individual transition consisting of an initial state a final state and a k-point is given here. Values of zero correspond to the inclusion of all initial and final states and all k-points and can be used as "wildcards" (default). Therefore, an empty element amounts to include all transitions. Select to include or exclude states. If a state is included as well as excluded several times the last definition (in the sequence of individual transitions) counts. Number of k-point to consider. A value of zero (default) means to include all k-points. Initial state of individual transition. A value of zero (default) means to include all states. Final state of individual transition. A value of zero (default) means to include all states. A list of ranges of transitions (initial state as well as final state ranges) and a k-point are given here. An empty list amounts to no transitions at all. A range of transitions (for initial as well as final states) is given here. A range consists of a "start" and a "stop" value as well as a k-point. Values of zero correspond to starting at the first state and stopping at the last state and considering all k-points. They can be used as "wildcards" (default). Therefore, an empty element corresponds to the full initial/final state range for all k-points. Select to include or exclude states. If a state is included as well as excluded several times the last definition (in the sequence of individual transitions) counts. Select for initial or final state range Number of k-point to consider. A value of zero (default) means to include all k-point. Start value (first state) for range. A value of zero (default) means to start from the first state. Stop value (last state) for range. A value of zero (default) means to stop at the last state (no upper limit). A list of initial and final state entries to be considered for transitions. An empty list amounts to no transitions at all. An initial or final state and corresponding k-point is given here. Values of zero correspond to considering all initial/final states for all k-points. They can be used as "wildcards" (default). Therefore, an empty element corresponds to the full initial/final state set for all k-points. Select to include or exclude states. If a state is included as well as excluded several times the last definition (in the sequence of individual transitions) counts. Select for initial or final state list Number of k-point to consider. A value of zero (default) means to include all k-point. The state to be considered. A value of zero (default) means to include all states. finite momentum transfer { \bf G}+{ \bf q} vector vgqlmt,nqptmt
    "true"
    if tetrahedron method is used for the k-space integration in the Kohn-Sham response function
    tetrakordexc tetracw1k tetraqweights choice of weights and nodes for tetrahedron method and non-zero Q-point
    number of points to be sampled linearly inside the energy interval energy interval for the density of states noreplace noreplace 301 Calculate eigenvectors, -values and occupancies 310 Calculate frequency-dependent weights for convolutions using the linear tetrahedron method 320 Calculate momentum matrix elements 330 Calculate q-dependent matrix elements 340 Calculate the Kohn-Sham response function checked in the code ! 345 Calculate the Kohn-Sham response function taking into account the rigid shift of the BSE diagonal. This is not a duplicate task, as the task-Nr. is referenced. checked in the code ! 350 Set up simple xc-kernels, solve Dyson's equation for the full polarizability and determine the macroscopic dielectric function and other spectroscopic quantities. 401 Calculate eigenvectors, -values and occupancies for screening 410 Calculate frequency-dependent weights for convolutions using the linear tetrahedron method for screening 420 Calculate momentum matrix elements for screening 430 Calculate RPA screening (ignoring scissor's shift) 440 Calculate direct term of BSE Hamiltonian 441 Calculate exchange term of BSE Hamiltonian 445 Bethe-Salpeter equation 450 Calculate frequency dependent xc-kernel drived from the Bethe-Salpeter equation in first order 23 estimate bandgap from regular grid 120 calculate momentum matrix elements (legacy) 121 linear optics (legacy) 321 ASCII output of momentum matrix elements 322 convert momentum matrix elements file to old format 331 ASCII output of q-dependent matrix elements 335 calculate matrix elements of the plane wave (simple version for checking) 339 check relation between matr. el. of exp. and mom. matr. el. 341 ASCII output of Kohn Sham response function 342 binary output of Kohn Sham response function 398 check ALDA kernel 451 BSE-kernel, straight forward version 499 degub routine of xs-part 700 estimate disk-space, cpu-time and memory requirements 701 test timing 999 debug routine main part of code 900 generate STATE.xml file from STATE.OUT file 901 generate STATE.OUT file from STATE.xml file 910 display Information about STATE.OUT file 911 display Information about STATE.xml file
    Type of matrix element generation (band-combinations). Should only be referenced for experimental features.
    "true"
    if also off-diagonal tensor elements for the interacting response function are to be calculated
    maximum angular momentum for APW functions for q-dependent matrix elements maximum angular momentum for Rayleigh expansion of {\bf q} -dependent plane wave factor energy cutoff for the unoccupied states in the Kohn-Sahm response function and screening Lorentzian broadening for all spectra smallest energy difference for which the square of its inverse will be considered in the Kohn-Sham response function
    "true"
    if energy outputs are in eV
    Should TDDFT be used or BSE if
    "true"
    , a fast method to calculate APW-lo, lo-APW and lo-lo parts of the momentum matrix elements in the muffin-tin is used.
    if
    "true"
    , a fast method to calculate APW-lo, lo-APW and lo-lo parts of the {\bf q} -dependent matrix elements in the muffin-tin is used.
    true if to append info to output file debugging level |G+q| cutoff for Kohn-Sham response function, screening and for expansion of Coulomb potential nosymxs nosym is
    "true"
    if no symmetry information should be used
    ngridkxs k-point grid sizes vkloffxs k-point offset reducekxs reducek is
    "true"
    if k-points are to be reduced (with crystal symmetries)
    ngridqxs q-point grid sizes reduceqxs reducek is
    "true"
    if q-points are to be reduced (with crystal symmetries)
    rgkmaxxs smallest muffin-tin radius times gkmax swidthxs width of the smooth approximation to the Dirac delta function (must be greater than zero) lmaxapwxs angular momentum cut-off for the APW functions lmaxmatxs angular momentum cut-off for the outer-most loop in the hamiltonian and overlap matrix setup nemptyxs number of empty states scissors correction
    The keywords tag can contain a space separated list of keywords classifying the calculation for archiving purposes. It is not used by the exciting program.
    This is the path to scratch space where the eigenvector files EVECFV.OUT, EVECSV.OUT and OCCSV.OUT will be written. If the local directory is accessed via a network then scrpath can be set to a directory on a local disk
    a q-point is given in reciprocal space coordinates This attribute is used to trigger lower-level tasks and is mainly used for testing, debugging, and the testing of new features. Do not use it unless you know what you are doing.