Input File Description

Program: d3hess.x / PWscf / Quantum ESPRESSO (version: 7.2)

TABLE OF CONTENTS

INTRODUCTION

&INPUT

prefix | outdir | filhess | step

INTRODUCTION

Purpose of d3hess.x:
  This is a post processing program to compute second derivatives of D3 dispersion in QE.

  The d3hess.x program should be run after an scf or relax calculation.
  It reads the molecular geometry from the xml file in the outdir and save
  the second derivatives matrix in a file on the disk.
  Afterwords, phonon reads the file and add the D3 Hessian matrix to the dynamical matrix with the proper phase (q),
  to include dispersion effects on vibrational frequencies.

  The workflow is just:

        (1) do an SCF
        (2) run d3hess
        (3) run phonon

  Please note that filhess in d3hess input and dftd3_hess in phonon input, if given, should match.

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

   &INPUT
     ...
   /
   

Namelist: &INPUT

prefix CHARACTER
Default: 'pwscf'
prefix of input file produced by pw.x
(wavefunctions are not needed)
         
outdir CHARACTER
Default: value of the ESPRESSO_TMPDIR environment variable if set; current directory ('./') otherwise
directory containing the input data, i.e. the same as in pw.x
         
filhess CHARACTER
Default: 'prefix.hess'
output file where the D3 hessian matrix is written
(should match dftd3_hess keyword in phonon calculation)
         
step REAL
Default: 1.d-3
 step for numerical differentiation in a.u.
         
This file has been created by helpdoc utility on Thu Mar 30 12:14:01 CEST 2023.