Input data format: { } = optional, [ ] = it depends, # = comment Structure of the input data: =============================================================================== &CONTROL ... / &WANNIER ... / &SCREEN ... / &HAM ... / K_POINTS { tpiba | automatic | crystal | gamma | tpiba_b | crystal_b | tpiba_c | crystal_c } if (gamma) nothing to read if (automatic) nk1, nk2, nk3, k1, k2, k3 if (not automatic) nks xk_x, xk_y, xk_z, wk if (tpipa_b or crystal_b in a 'bands' calculation) see Doc/brillouin_zones.pdf 'pwscf' Prepended to input/output filenames; must be the same used in the previous PW calculations. current directory ('./') Directory containing input, output, and scratch files; must be the same as specified in the calculation of previous PW calculation. ' ' Specify the KCW calculation to be done Possible choices: Pre-processing to prepare KCW calculation. Read previous PWSCF and possibly W90 outputs and prepare the KCW calculation Perform the calculation of KCW screening coefficient using a LR approach as described here https://doi.org/10.1021/acs.jctc.7b01116 and arXiv:2202.08155 Perform the calculation interpolation and diagonalization of the KI hamiltonian Computes the (estimated) q+G=0 contribution to the bare and screened KC corrections. A report on this quantities is printed on output and can be used to correct a posteriori a "screen" calculation performed without any corrective scheme (l_vcut=.false.) avoiding the need of re-doing a "screen" calculation. 1 = 0 : minimal output = 1 : as above + performs additional checks. > 1 : as above + additional infos on all the steps. .TRUE. If true the KS canonical orbitals are used instead of Wannier functions. It makes sense for isolated system only. .FALSE. If true read the Unitary matrix written by Wannier90. Implicitely means a previous wannier90 calculation was performed and a KCW calculation will be performed starting from MLWF. Requires 'write_hr = .true.' in wannier90. 0.0001 Ry HARD-CODED FOR NOW. Two or more Wannier functions are considered identical if their spread (self-hartree) differ by less than spread_thr. Requires check_spread = .true. FALSE If kcw_at_ks = .TRUE. only the screening paramenter for the HOMO is calculated. Mainly for a perturbative calculation of the first Ionization Potential in isolated systems. FALSE If .TRUE. the Gygi-Baldereschi scheme is used to deal with the q->0 divergence of the Coulomb integral (bare and screened). Improves the convergence wrt k/q-point sampling. Requires to correctly set eps_inf for the calculation of the screened interaction. Use it only for periodic system. For isoleted system use assume_isolated, instead. 'none' Used to perform calculation assuming the system to be isolated (a molecule or a cluster in a 3D supercell). Currently available choices: (default): regular periodic calculation w/o any correction. Martyna-Tuckerman correction to both total energy and scf potential. Adapted from: G.J. Martyna, and M.E. Tuckerman, "A reciprocal space based method for treating long range interactions in ab-initio and force-field-based calculation in clusters", J. Chem. Phys. 110, 2810 (1999), doi:10.1063/1.477923. 1 Which spin channel to calculate (only collinear calculation). 1 = spin up channel 2 = spin down channel It has to be consistent with the previous Wannier90 calculation (see 'spin' keyword in Wannier90 documentation) -1,-1,-1 Parameters of the Monkhorst-Pack grid (no offset). Same meaning as for nk1, nk2, nk3 in the input of pw.x. It has to coincide with the regular mesh used for the wannier90 calculation. .FALSE. If .true. the response function is computed neglecting xc effects both in the kernel and in the response function (RPA). .FALSE. If .true. write wannier orbital densities in single-precision. .FALSE. If .true. write Wannier orbital densities and Wannier functions in real space. .FALSE. If .true. compute and use the symmetries of the Wannier orbital densities to reduce the number of k and q points for the BZ sampling. .FALSE. If .true. allow to use symmetries that send the Wannier orbital density into the Wannier translated by a lattice vector (wcf= wannier center translation) to further reduce the number of q points wann The seedname of the previous Wannier90 calculation for occupied states. NOTA BENE: the code implicitely assumed that the seedname for empty state is the same as that for occupied state with "_emp" appended. Keep this in mind when set up the wannier90 inputs. For example: wann.win is the wannier90 input file for the occupied states. wann_emp.win is the wannier90 input file for the empty states. 0 The number of wannier function for the occupied manifold. It has to coincide with the number of occupied KS orbitals. The whole KS manifold has to be wannierised (no 'exclude_band' option for occupied state, at the moment). 0 The number of wannier function for the empty manifold. It has to coincide with the number of empty wannier function from the previous wannier90 calculation FALSE If true empty state are computed. Require a previous wannier90 calculation for the empty manifold. The code search for the unitary matrices in the wannier90 file seedname_emp_u.mat FALSE Specify if a disentangle unitary matrix needs to be read. Requires a consisten calcuation from the previous wannier90 run. FALSE Specify if a diagonalization of the KS matrix build using the wannier function in input has to be performed. This is mainly for debugging purpose. alpha_mix(1)=0.7 Mixing factor (for each iteration) for updating the scf potential: vnew(in) = alpha_mix*vold(out) + (1-alpha_mix)*vold(in) maxter=100 Maximum number of iterations in a scf step. If you want more than 100, edit variable "maxter" in PH/phcom.f90 4 Number of iterations used in potential mixing. 1e-14 Threshold for self-consistency. -1 Perform the screening calculation for a particular orbital. If i_orb = -1 (default) all the orbitals are computed. Assumes values between 1 and the total number of wannier functions. 1.d0 The macroscopic dielectric constant. Needed for the Gygi-Baldereschi scheme if l_vcut = .TRUE. Typically from exp or from a ph.x calculation. NOTA BENE: This would be equivalent to a Makov-Payne correction. It works well for cubic systems. Less well for anisotropic systems. ANISOTROPIC SYSTEMS: In this case a generalization of the GB scheme is implemented based on Nano Lett.,9, 975 (2009). It requires the full dielectric tensor to be provided. The code searches (in the working dir) for a file named "eps.dat" containing the macrospocic dielectric tensor. If it does not find it, the value eps_inf provided in input will be used (isotropic approximation). If not even eps_inf is provided in input no correction is applied to the screened KC correction. .FALSE. If .TRUE. the spread (self-hartree) of the Wannier functions is checked and used to decide whether two or more Wannier functions can be considered "identical" or not. Two Wannier functions are considered identical if their spread (self-hartree) differ by less than 1e-4 Ry (Hard coded for now, see spread_thr). .FALSE. If .true. the interpolated band structure is computed along a path specified with the K_POINTS card ( see PW documentation https://www.quantum-espresso.org/Doc/INPUT_PW.html#K_POINTS ) .TRUE. If .true. the position of the Wannier function inside the cell is used to set the proper distance and to have a smoother interpolation. Requires seedname_centres.xyz to be printed by the previous Wannier90 run. If the file is not found it is automatically switched to .FALSE. and only the distance between the cells is used (see also Wannier90 documentation) .TRUE. If .true. the KCW hamiltonain in the Wannier basis and in real spase H(R)_m_n is printed to file. Usefull for furhter post-processing. .FALSE. If .true. only the on-site and diagonal elements of the KCW hamiltonain are computed (R=0 and n=m). see https://www.quantum-espresso.org/Doc/INPUT_PW.html#K_POINTS