View source for Explanations for C2H2 rt response input files-v0

== required and recommended variables ==

=== &unit ===

Mandatory: none

 &units
   unit_length='Angstrom'
   unit_energy='eV'
   unit_time='fs'
 /

This namelist specifies the unit system used in the "input" file. 
If you do not specify the units for some physical quantities, atomic unit will be used for those quantities.

For isolated systems (specified by <code>iperiodic = 0</code> in <code>&system</code>), the units of output files are basically Angstrom/eV/fs at the present.

=== &calculation ===

Mandatory: calc_mode

 &calculation
   calc_mode = 'RT'
 /

The variable <code>calc_mode</code> should be one of <code>'GS'</code>, <code>'RT'</code>, and <code>'GS-RT'</code>. 
Note that the ground state (<code>'GS'</code>) and real time (<code>'RT'</code>) calculations should be done separately and sequentially for isolated systems (specified by <code>iperiodic = 0</code> in <code>&system</code>). 
For periodic systems (specified by <code>iperiodic = 3</code> in <code>&system</code>), both ground state and real time calculations should be carried out as a single task (<code>calc_mode = 'GS_RT'</code>).

=== &control ===

Mandatory: none

 &control
   sysname = 'C2H2'
 /

'C2H2' defined by <code>surname = 'C2H2'</code> will be used in the filenames of output files.

=== &system ===

Mandatory: iperiodic, al, nstate, nelem, natom

 &system
   iperiodic = 0
   al = 16d0, 16d0, 16d0
   nstate = 5
   nelem = 2
   natom = 4
   nelec = 10
 /

<code>iperiodic = 0</code> indicates that isolated boundary condition is assumed. 
<code>al = 16d0, 16d0, 16d0</code> specifies the lengths of three sides of a rectangular parallelepiped where the grid points are prepared. 
<code>nstate = 8</code> indicates the number of Kohn-Sham orbitals to be solved. 
<code>nelec = 10</code> indicate the number of valence electrons in the system.
<code>nelem = 2</code> and <code>natom = 4</code> indicate the number of elements and the number of atoms in the system, respectively.

=== &pseudo ===

Mandatory: pseudo_file, iZatom

 &pseudo
   iZatom(1)=6
   iZatom(2)=1
   pseudo_file(1)='C_rps.dat'
   pseudo_file(2)='H_rps.dat'
   Lmax_ps(1)=1
   Lmax_ps(2)=0
   Lloc_ps(1)=1
   Lloc_ps(2)=0
 /

Information on pseudopotentials. 
<code>iZatom(1) = 6</code> indicates the atomic number of the element 1.
<code>pseudo_file(1) = 'C_rps.dat'</code> indicates the filename of the pseudopotential of element 1. 
<code>Lmax_ps(1) = 1</code> and <code>Lloc_ps(1) = 1</code> indicate the maximum angular momentum of the pseudopotential projector and the angular momentum of the pseudopotential that will be treated as local, respectively. 

=== &tgrid ===

Mandatory: dt, Nt

  & tgrid
   dt=1.25d-3
   nt=5000
/

<code>dt=1.25d-3</code> specifies the time step of the time evolution calculations.
<code>nt=5000</code> specifies the number of time steps in the calculation.

=== &emfield ===

Mandatory: ae_shape1

 &emfield
   ae_shape1 = 'impulse'
   epdir_re1 = 0.d0,0.d0,1.d0
 /

This is a sample to calculate polarizability and oscillator distribution from real-time electron dynamics calculations.
Specifying <code>ae_shape1 = 'impulse'</code>, a weak impulsive force is applied to the isolated matter at ''t=0''
In output files, the polarizability and oscillator strength distribution, which is related to the imaginary part of the polarizability will be included.

=== &atomic_coor ===

Mandatory: none

 &atomic_coor
 'C'    0.000000    0.000000    0.599672  1
 'H'    0.000000    0.000000    1.662257  2
 'C'    0.000000    0.000000   -0.599672  1
 'H'    0.000000    0.000000   -1.662257  2
 /

List of atomic coordinates. Last column corresponds to kinds of elements.

== additional options ==

=== &parallel ===

Mandatory: none

 &parallel
   nproc_ob = 1
   nproc_domain = 1,1,1
   nproc_domain_s = 1,1,1
 /

Followings are explanation of each variable.
* <code>nproc_ob</code>: Number of MPI parallelization for orbitals that related to the wavefunction calculation.
* <code>nproc_domain(3)'</code>: Number of MPI parallelization for each direction in real-space that related to the wavefunction calculation.
* <code>nproc_domain_s(3)'</code>: Number of MPI parallelization for each direction in real-space that related to the electron density calculation.

Defaults are <code>0</code> for <code>nproc_ob</code>, <code>(0/0/0)</code> for <code>nproc_domain</code>, and <code>(0/0/0)</code> for <code>nproc_domain_s</code>. If users use the defauls, automatic proccess assignment is done. Users can also specify <code>nproc_ob</code>, <code>nproc_domain</code>, and <code>nproc_domain_s</code> manually. In that case, followings must be satisfied.
* nproc_ob</code> * <code>nproc_domain(1)</code> * <code>nproc_domain(2)</code>* <code>nproc_domain(3)</code>=total number of processors
* <code>nproc_domain_s(1)</code> * <code>nproc_domain_s(2)</code>* <code>nproc_domain_s(3)</code>=total number of processors
* <code>nproc_domain_s(1)</code> is a multiple of <code>nproc_domain(1)</code>
* <code>nproc_domain_s(2)</code> is a multiple of <code>nproc_domain(2)</code>
* <code>nproc_domain_s(3)</code> is a multiple of <code>nproc_domain(3)</code>

=== &hartree ===

Mandatory: none

 &hartree
   meo = 3
   num_pole_xyz = 2,2,2
 /

<code>meo</code> specifies the order of multipole expansion of electron density that is used to prepare boundary condition for the Hartree potential. 
* <code>meo=1</code>: Single pole is set.
* <code>meo=2</code>: Multipoles are set to the position of atoms. 
* <code>meo=3</code>: Multipoles are set to the center of mass of electrons in cuboids.
<code>num_pole_xyz(3)</code> are number of multipoles when <code>meo</code> is <code>3</code>. A default for <code>meo</code> is <code>3</code>, and defaults for <code>num_pole_xyz</code> are <code>(0,0,0)</code>. When default is set, number of multipoles is calculated automatically.

=== &analysis ===

Mandatory: none

 &analysis
   out_psi = 'y'
   out_dns = 'y'
   out_dos = 'y'
   out_pdos = 'y'
   out_elf = 'y'
 /

These namelists specify the output files.