Variables: Difference between revisions

From The Yambo Project
Jump to navigation Jump to search
No edit summary
No edit summary
Line 35: Line 35:
{{var2|NGBlkXd/Xs|RL/Energy|Integer/Real|Number of G-vectors or energy cut off in the screening.|Determines the size of the dielectric matrix in G-space. Needed for inclusion of local field effects. It should be much smaller than the number of G-vectors needed to expand the wavefunctions. It needs careful convergence.  }}
{{var2|NGBlkXd/Xs|RL/Energy|Integer/Real|Number of G-vectors or energy cut off in the screening.|Determines the size of the dielectric matrix in G-space. Needed for inclusion of local field effects. It should be much smaller than the number of G-vectors needed to expand the wavefunctions. It needs careful convergence.  }}
</span>
</span>
<span id="ETStpsX">  <!--single variable anchor-->
<span id="QpntsRX">  <!--single variable anchor-->
{{var2|ETStpsX|None|Integer|Number of energy steps.|Determines the number of steps in energy the response function/spectrum is computed for in the desired range defined by EnRngeX. }}
{{var2|QpntsRXd/Xs|None|Integer range|Range of indexes of q-points/transferred momenta to be computed|Set to 1 1 to select just the '''q=0''' term.}}
</span>
<span id="BndsRnX">  <!--single variable anchor-->
{{var2|BndsRnXd/Xs|None|Integer range|Range of bands included in the sum.|Range of bands incluein blah blah }}
</span>
</span>
<span id="EnRngeX">  <!--single variable anchor-->
<span id="EnRngeX">  <!--single variable anchor-->
{{var2|EnRngeXd/Xs|Energy|Range|Energy range the spectrum is calculated across.|Energy range blah blah }}
{{var2|EnRngeXd/Xs|Energy|Range|Energy range the spectrum is calculated across.|Energy range blah blah }}
</span>
</span>
 
<span id="DmRngeX">  <!--single variable anchor-->
{{var2|DmRngeXd/Xs|Energy|Range|Determines the damping used across the requested spectral range.|Typically this is kept constant. If different values are used, the damping at each energy will be interpolated linearly. This can be useful when poor k-point sampling leads to large oscillations at higher energy.}}
</span>
<span id="ETStpsX">  <!--single variable anchor-->
{{var2|ETStpsX|None|Integer|Number of energy steps.|Determines the number of steps in energy the response function/spectrum is computed for in the desired range defined by EnRngeX. }}
</span>
<span id="LongDrX">  <!--single variable anchor-->
<span id="LongDrX">  <!--single variable anchor-->
{{var2|LongDrXd/Xs|Length|Vector|Electric field direction.|Electric field direction}}
{{var2|LongDrXd/Xs|Length|Vector|Electric field direction.|Electric field direction}}
</span>
</span>


<span id="BndsRnX">  <!--single variable anchor-->
===Optics-advanced===<!--section anchor-->  '''Here anything needing verbosity'''
{{var2|BndsRnXd/Xs|None|Integer range|Range of bands included in the sum.|Range of bands incluein blah blah }}
<span id="FFTGvecs">  <!--single variable anchor-->
{{var2|FFTGvecs|RL/Energy|Integer/Real|Number of G-vectors or energy cut off for expanding the wavefunctions/FFT transforms| It needs careful convergence. Determines the memory needed.}}
</span>
</span>
<span id="DrudeWX">  <!--single variable anchor-->
<span id="DrudeWX">  <!--single variable anchor-->
{{var2|DrudeWXd/Xs|Energy|Complex|Drude plasmon energy and inverse lifetime.|Drudes }}
{{var2|DrudeWXd/Xs|Energy|Complex|Drude plasmon energy and inverse lifetime.|Drudes }}
</span>
</span>


Chimod= "IP"                # [X] IP/Hartree/ALDA/LRC/BSfxc
NGsBlkXd= 1            RL    # [Xd] Response block size
% QpntsRXd
  1 | 14 |                  # [Xd] Transferred momenta
%
% BndsRnXd
  1 | 100 |                # [Xd] Polarization function bands
%
% EnRngeXd
  0.00000 | 10.00000 | eV    # [Xd] Energy range
%
% DmRngeXd
  0.10000 |  0.10000 | eV    # [Xd] Damping range
%
ETStpsXd= 100                # [Xd] Total Energy steps
% LongDrXd
1.000000 | 0.000000 | 0.000000 |        # [Xd] [cc] Electric Field
%
===Optics-advanced===<!--section anchor-->  '''Here anything needing verbosity'''
<span id="FFTGvecs">  <!--single variable anchor-->
{{var2|FFTGvecs|RL/Energy|Integer/Real|Number of G-vectors or energy cut off for expanding the wavefunctions/FFT transforms| It needs careful convergence. Determines the memory needed.}}
</span>


===Coulomb cutoff===
===Coulomb cutoff===

Revision as of 10:12, 28 March 2017

Just playing with variable templates

Var1 Var2 Var3 - no units

Units

  • None = no unit
  • RL = number of G-vectors
  • Energy = Ha, mHa (Hartree atomic units), Ry, mRy (Rydberg atomic units), eV, meV (electron volts), K, THz, GHz
  • Length = Bohr atomic units a.u.

Formats

  • Integer = integer value
  • Real = real value
  • Complex = ( real part , imag part )
  • String = string
  • Range = Lower limit | Upper limit |(in the specified Unit)
  • Integer range = Lower limit | Upper limit (integer values)
  • Vector = x | y | z | (in Cartesian coordinates, sandwiched by %)

Ranges can also be split on multiple lines.

Initialization

Variable: MaxGvecs (Units: RL/Energy) Meaning: Number of G-vectors in screening
Tip: This determines the size of the dielectric matrix in G-space. Needed for inclusion of local field effects. It should be much smaller than the number of G-vectors needed to expand the wavefunctions. It needs careful convergence.

Optics-basic

Chimod (Units: None, Format: String)
Meaning: Type of kernel in TDDFT Dyson equation.
Tip: Do not set this manually - set using the appropriate -k command line option. Allowed values: IP/Hartree/ALDA/LRC/BSfxc. IP indicates no kernel (independent particle level/RPA without local fields).

NGBlkXd/Xs (Units: RL/Energy, Format: Integer/Real)
Meaning: Number of G-vectors or energy cut off in the screening.
Tip: Determines the size of the dielectric matrix in G-space. Needed for inclusion of local field effects. It should be much smaller than the number of G-vectors needed to expand the wavefunctions. It needs careful convergence.

QpntsRXd/Xs (Units: None, Format: Integer range)
Meaning: Range of indexes of q-points/transferred momenta to be computed
Tip: {{{5}}}

BndsRnXd/Xs (Units: None, Format: Integer range)
Meaning: Range of bands included in the sum.
Tip: Range of bands incluein blah blah

EnRngeXd/Xs (Units: Energy, Format: Range)
Meaning: Energy range the spectrum is calculated across.
Tip: Energy range blah blah

DmRngeXd/Xs (Units: Energy, Format: Range)
Meaning: Determines the damping used across the requested spectral range.
Tip: Typically this is kept constant. If different values are used, the damping at each energy will be interpolated linearly. This can be useful when poor k-point sampling leads to large oscillations at higher energy.

ETStpsX (Units: None, Format: Integer)
Meaning: Number of energy steps.
Tip: Determines the number of steps in energy the response function/spectrum is computed for in the desired range defined by EnRngeX.

LongDrXd/Xs (Units: Length, Format: Vector)
Meaning: Electric field direction.
Tip: Electric field direction

===Optics-advanced=== Here anything needing verbosity

FFTGvecs (Units: RL/Energy, Format: Integer/Real)
Meaning: Number of G-vectors or energy cut off for expanding the wavefunctions/FFT transforms
Tip: It needs careful convergence. Determines the memory needed.

DrudeWXd/Xs (Units: Energy, Format: Complex)
Meaning: Drude plasmon energy and inverse lifetime.
Tip: Drudes


Coulomb cutoff

CutRadius (Units: Length, Format: Real)
Meaning: Sphere/cylinder radius.
Tip: TIP

CUTBox (Units: Length, Format: Vector)
Meaning: Box sides.
Tip: BOX

CUTGeo (Units: None, Format: String)
Meaning: Cutoff geometry.
Tip: Allowed values are: box/cylinder/sphere X/Y/Z/XY...

GW

Variable: EXXRLvcs (Units: RL) Meaning: Number of G-vectors used in the sum of the exchange self-energy Sx.
Tip: It needs careful convergence: not particularly time consuming, large values can be used to ensure convergence.

Variable: QPkrange (Units: Integers) Meaning: First and last Indexes of kpoints and bands the slef energy correction is calculated
Tip: If interested in non consecutive kpoints or bands multiple rows can be also considered

Retrieved from "https://wiki.yambo-code.eu/wiki/index.php?title=Variables&oldid=721"