View source for Explanations for Si ms input files

== Unit system ==

Hartree atomic units are employed in this calculation by default.

== &calculation ==


  &calculation
    calc_mode = 'GS_RT'
    use_ms_maxwell = 'y'
  /

The variable <code>calc_mode</code> is set to be <code>'GS_RT'</code> mode, which executes the ground state (GS) and real-time (RT) calculation  with single calculation task.
<pre>use_ms_maxwell='y'</pre> indicates the multiscale Maxwell-TDDFT calculation mode.

== &control ==

  &control
    sysname = 'Si'
  /

The variable <code>sysname</code> is set to be <code>'Si'</code>, which is the filename prefix of the outputs.



== &system ==


  &system
    iperiodic = 3
    al = 10.26d0,10.26d0,10.26d0
    isym = 8 
    crystal_structure = 'diamond'
    nstate = 32
    nelec = 32
    nelem = 1
    natom = 8
  /

<code>iperiodic = 3</code> indicates that three dimensional periodic boundary condition (bulk crystal) is supposed.
<code>al = 10.26d0, 10.26d0, 10.26d0</code> specifies the lattice constans of the unit cell crystaline.
The variable <code>isym</code> indicates the symmetry in the unit cell.
Considering the bulk silicon crystal with the applied electric field parallel to the one lattice axis, <code>  isym = 8 </code> is desirable to speed up the calculation.
For more information, see [[Symmetry group of crystalline]].
<code>crystal_structure = 'diamond'</code> indicate the crystal structure of the considered material.
<code>nstate = 32</code> indicates the number of Kohn-Sham orbitals in the computation.
<code>nelec = 32</code> is the number of valence electrons in the system.
<code>nelem = 1</code> and <code>natom = 8</code> is the number of elements and the number of atoms in the system, respectively.

== &pseudo ==


  &pseudo
    iZatom(1)=14
    pseudo_file(1) = './Si_rps.dat'
    Lloc_ps(1)=2
  /

<code>iZatom(1) = 14</code> is  the number of atoms for the element 1.
<code>pseudo_file(1) = 'Si_rps.dat'</code> is the filename of the pseudopotential of element 1. 
<code>Lloc_ps(1) = 1</code> indicate the angular momentum of the pseudopotential.

== &functional ==

  &functional
    xc ='PZ'
  /

<code>xc ='PZ'</code> specifies the type of exchange correlation potential as LDA. 




== &rgrid ==

  &rgrid
    num_rgrid = 12,12,12
  /

<code>num_rgrid=12,12,12</code> specifies number of the real space grids for single crystal calculation.


== &kgrid ==

  &kgrid
    num_kgrid = 2,2,2
  /

<code>num_kgrid=2,2,2</code> specifies number of the k-space grids for single crystal calculation.


== &tgrid ==

&tgrid
 nt=4000
 dt=0.08  
/

<code>dt=0.16</code> sets the time step of the time-evolution calculations.
<code>Nt=3000</code> is the number of time steps in the calculation.

== &propagation ==

propagation
  propagator='middlepoint'
/


<code>propagation='middlepoint'</code> specifies the numerical mathod of the time-evolution of the wave function.

== &scf ==

  &scf
    ncg = 5
    nscf = 100
  /

<code>ncg = 5</code> is the number of conjucate gradient step in the single scf calculation, and <code>nscf = 100</code> specifies the number of the SCF step.

== &emfield ==

  &emfield
    ae_shape1 = 'Acos2'
    rlaser_int1 = 1d12
    pulse_tw1 = 441.195136248d0
    omega1 = 0.05696145187d0
    epdir_re1 = 0.,0.,1.
  /

<code>ae_shape1 = 'Acos2'</code> specifies the pulse shape of the electric field, having cos-square envelope.
<code>laser_int1</code> specifies maximum intensity of the applied electric field in unit of W/cm^2.
<code>epdir_re1 = 0,0,1</code> identifies the unit vector of polarization direction. 
Specifying the real part of the polarization vector by 'epdir_re1', linear polarization is assumed. 
Using both the real ('epdir_re1') and imaginary ('epdir_im1') parts of the polarization vector, circularly (and general ellipsoidally) polarized pulses may also be described. 

<code>omega1</code> specifies photon energy (frequency multiplied with hbar).
<code>pulse_tw1</code> sets the pulse duration.
Note that it is not FWHM but a full duration of the sine-square envelope.
<code>phi_cep1</code> specifies the carrier envelope phase of the pulse.
It is possible to have two pulses simultaneously to simulate pump-probe experiments, adding information for two pulses. 
The time delay can be indicated using the variable 't1_t2'.

== &multiscale ==

  &multiscale
    fdtddim = '1D'
    twod_shape = 'periodic'
    nx_m  = 4
    ny_m  = 1
    hX_m = 250d0
    nksplit = 2
    nxysplit = 1
    nxvacl_m = -2000
    nxvacr_m = 256
  /

<code>fdtddim</code> specifies the dimension of the macro system. In the case of <code>fdtddim='1D'</code>, the one-dimensional light propagation in the slab region.
<code>twod_shape = 'periodic'</code> specifies the boundary condition of the EM field. 
<code>nx_m, ny_m</code> is the number of the macroscopic grids for the x and y-direction, respectively.
<code>  nxvacl_m, nxvacr_m </code> indicates the number of the additional cells connected on the left-side and right-side of the material's surface.




== &atomic_coor ==

 &atomic_coor
  'Si'    .0    .0    .0    1
  'Si'    .25    .25    .25    1
  'Si'    .5    .0    .5    1
  'Si'    .0    .5    .5    1
  'Si'    .5    .5    .0    1
  'Si'    .75    .25    .75    1
  'Si'    .25    .75    .75    1
  'Si'    .75    .75    .25    1
 /

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