    ------------------------------------------------------------------------
    INPUT FILE DESCRIPTION

    Program: hp.x / PWscf / Quantum Espresso (version: 6.6)
    ------------------------------------------------------------------------

    Input data format: { } = optional, [ ] = it depends, # = comment

    Structure of the input data:
    ===============================================================================

    &INPUTHP
       ...
    /

    ========================================================================
    NAMELIST: &INPUTHP

       +--------------------------------------------------------------------
       Variable:       prefix

       Type:           CHARACTER
       Default:        'pwscf'
       Description:    Prepended to input/output filenames; must be the same
                       used in the calculation of unperturbed system.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       outdir

       Type:           CHARACTER
       Default:        value of the ESPRESSO_TMPDIR environment variable if set;
                        current directory ('./') otherwise
       Description:    Directory containing input, output, and scratch files;
                       must be the same as specified in the calculation of
                       the unperturbed system.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       iverbosity

       Type:           INTEGER
       Default:        1
       Description:    = 1 : minimal output
                       = 2 : as above + symmetry matrices, final response
                             matrices chi0 and chi1 and their inverse matrices,
                             full U matrix
                       = 3 : as above + various detailed info about the NSCF
                             calculation at k and k+q
                       = 4 : as above + response occupation matrices at every
                             iteration and for every q point in the star
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       max_seconds

       Type:           REAL
       Default:        1.d7
       Description:    Maximum allowed run time before the job stops smoothly.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variables:      nq1, nq2, nq3

       Type:           INTEGER
       Default:        1,1,1
       Description:    Parameters of the Monkhorst-Pack grid (no offset).
                       Same meaning as for nk1, nk2, nk3 in the input of pw.x.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       skip_equivalence_q

       Type:           LOGICAL
       Default:        .false.
       Description:    If .true. then the HP code will skip the equivalence
                       analysis of q points, and thus the full grid of q points
                       will be used. Otherwise the symmetry is used to determine
                       equivalent q points (star of q), and then perform
                       calculations only for inequivalent q points.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       determine_num_pert_only

       Type:           LOGICAL
       Default:        .false.
       See:            find_atpert
       Description:    If .true. determines the number of perturbations
                       (i.e. which atoms will be perturbed) and exits smoothly
                       without performing any calculation. For DFT+U+V, it also
                       determines the indices of inter-site couples.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       find_atpert

       Type:           INTEGER
       Default:        1
       Description:    Method for searching of atoms which must be perturbed.
                       1 = Find how many inequivalent Hubbard atoms there are
                           by analyzing unperturbed occupations.
                       2 = Find how many Hubbard atoms to perturb based on
                           how many different Hubbard atomic types there are.
                           Warning: atoms which have the same type but which
                           are inequivalent by symmetry or which have different
                           occupations will not be distinguished in this case
                           (use option 1 or 3 instead).
                       3 = Find how many inequivalent Hubbard atoms
                           there are using symmetry. Atoms which have the
                           same type but are not equivalent by symmetry will
                           be distinguished in this case.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       docc_thr

       Type:           REAL
       Default:        5.D-5
       Description:    Threshold for a comparison of unperturbed occupations
                       which is needed for the selection of atoms which must
                       be perturbed. Can be used only when "find_atpert" = 1.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       skip_type(i), i=1,ntyp

       Type:           LOGICAL
       Default:        skip_type(i) = .false.
       See:            equiv_type
       Description:    "skip_type"(i), where i runs over types of atoms.
                       If "skip_type"(i)=.true. then no linear-response
                       calculation will be performed for the i-th atomic type:
                       in this case "equiv_type"(i) must be specified, otherwise
                       the HP code will stop. This option is useful if the
                       system has atoms of the same type but opposite spin
                       pollarizations (anti-ferromagnetic case).
                       This keyword cannot be used when "find_atpert" = 1.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       equiv_type(i), i=1,ntyp

       Type:           INTEGER
       Default:        equiv_type(i) = 0
       See:            skip_type
       Description:    "equiv_type"(i), where i runs over types of atoms.
                       "equiv_type"(i)=j, will make type i equivalent to type j
                       (useful when nspin=2). Such a merging of types is done
                       only at the post-processing stage.
                       This keyword cannot be used when "find_atpert" = 1.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       perturb_only_atom(i), i=1,ntyp

       Type:           LOGICAL
       Default:        perturb_only_atom(i) = .false.
       See:            compute_hp
       Description:    If "perturb_only_atom"(i)=.true. then only the i-th
                       atom will be perturbed and considered in the run.
                       This variable is useful when one wants to split
                       the whole calculation on parts.

                       Note: this variable has a higher priority than "skip_type".
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       start_q

       Type:           INTEGER
       Default:        1
       See:            last_q, sum_pertq
       Description:    Computes only the q points from "start_q" to "last_q".

                       IMPORTANT: "start_q" must be smaller or equal to
                       the total number of q points found.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       last_q

       Type:           INTEGER
       Default:        number of q points
       See:            start_q, sum_pertq
       Description:    Computes only the q points from "start_q" to "last_q".

                       IMPORTANT: "last_q" must be smaller or equal to
                       the total number of q points found.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       sum_pertq

       Type:           LOGICAL
       Default:        .false.
       See:            start_q, last_q, perturb_only_atom
       Description:    If it is set to .true. then the HP code will collect
                       pieces of the response occupation matrices for all
                       q points. This variable should be used only when
                       "start_q", "last_q" and "perturb_only_atom" are used.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       compute_hp

       Type:           LOGICAL
       Default:        .false.
       See:            perturb_only_atom
       Description:    If it is set to .true. then the HP code will collect
                       pieces of the chi0 and chi matrices (which must have
                       been produced in previous runs) and then compute
                       Hubbard parameters. The HP code will look for files
                       tmp_dir/HP/prefix.chi.i.dat. Note that all files
                       prefix.chi.i.dat (where i runs over all perturbed
                       atoms) must be placed in one folder tmp_dir/HP/.
                       "compute_hp"=.true. must be used only when the
                       calculation was parallelized over perturbations.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       conv_thr_chi

       Type:           REAL
       Default:        1.D-5
       Description:    Convergence threshold for the response function chi,
                       which is defined as a trace of the response
                       occupation matrix.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       thresh_init

       Type:           REAL
       Default:        1.D-14
       Description:    Initial threshold for the solution of the linear
                       system (first iteration). Needed to converge the
                       bare (non-interacting) response function chi0.
                       The specified value will be multiplied by the
                       number of electrons in the system.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       ethr_nscf

       Type:           REAL
       Default:        1.D-11
       Description:    Threshold for the convergence of eigenvalues during
                       the iterative diagonalization of the Hamiltonian in
                       the non-self-consistent-field (NSCF) calculation at
                       k and k+q points. Note, this quantity is NOT extensive.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       niter_max

       Type:           INTEGER
       Default:        100
       Description:    Maximum number of iterations in the iterative
                       solution of the linear-response Kohn-Sham equations.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       alpha_mix(i)

       Type:           REAL
       Default:        alpha_mix(1)=0.3
       Description:    Mixing parameter (for the i-th iteration) for updating
                       the response SCF potential using the modified Broyden
                       method. See: D.D. Johnson, PRB 38, 12807 (1988).
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       nmix

       Type:           INTEGER
       Default:        4
       Description:    Number of iterations used in potential mixing
                       using the modified Broyden method. See:
                       D.D. Johnson, PRB 38, 12807 (1988).
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       num_neigh

       Type:           INTEGER
       Default:        6
       Description:    Number of nearest neighbors of every Hubbard atom which
                       will be considered when writting Hubbard V parameters to
                       the file parameters.out, which can be used in the
                       subsequent DFT+U+V calculation. This keyword is used only
                       when lda_plus_u_kind = 2 (post-processing stage).
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       lmin

       Type:           INTEGER
       Default:        2
       Description:    Minimum value of the orbital quantum number of the Hubbard
                       atoms starting from which (and up to the maximum l in the
                       system) Hubbard V will be written to the file parameters.out.
                       "lmin" refers to the orbital quantum number of the atom
                       corresponding to the first site-index in Hubbard_V(:,:,:).
                       This keyword is used only when lda_plus_u_kind = 2 and only
                       in the post-processing stage. Example: "lmin"=1 corresponds to
                       writing to file V between e.g. oxygen (with p states) and its
                       neighbors, and including V between transition metals (with d
                       states) and their neighbors. Instead, when "lmin"=2 only the
                       latter will be written to parameters.out.
       +--------------------------------------------------------------------

       +--------------------------------------------------------------------
       Variable:       rmax

       Type:           REAL
       Default:        100.D0
       Description:    Maximum distance (in Bohr) between two atoms to search
                       neighbors (used only at the postprocessing step when
                       lda_plus_u_kind = 2). This keyword is useful when there
                       are e.g. defects in the system.
       +--------------------------------------------------------------------

    ===END OF NAMELIST======================================================

    This file has been created by helpdoc utility on Wed Dec 02 08:04:42 CET 2020