TDTimeStep
TDTimeStep
Section Time-Dependent::Propagation
Type float
The time-step for the time propagation. For most propagators you
want to use the largest value that is possible without the
evolution becoming unstable.
The default value is the maximum value that we have found
empirically that is stable for the spacing $h$:
$dt = 0.0426 - 0.207 h + 0.808 h^2$
(from parabolic fit to Fig. 4 of http://dx.doi.org/10.1021/ct800518j,
probably valid for 3D systems only).
However, you might need to adjust this value.
Source information
td/td.F90 : 231
call parse_variable(namespace, 'TDTimeStep', default_dt, td%dt, unit = units_inp%time)
Featured in tutorials
Featured in chapters of the manual:
Featured in testfiles
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- finite_systems_3d/29-pcm_chlorine_anion.02-td_prop-n60.inp
- finite_systems_3d/32-tdpcm_methane.02-td_prop_neq.inp
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- maxwell/01-free-propagation.02-2_pulses_td.inp
- maxwell/02-external-current.01-gaussian_current_pulse.inp
- maxwell/02-external-current.02-gaussian_current_pulse_with_pml.inp
- maxwell/02-external-current.03-gaussian_current_pulse_with_mask.inp
- maxwell/05-plane_waves.01-pulse_pml.inp
- maxwell/06-circular-polarization.01-1_puse_circ_pol.inp
- maxwell/07-mode-resolved-maxwell-ks-propagation.02-kick-of-the-electronic-subsystem.inp
- modelmb/01-cosh_2e_1d.02-td.inp
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- multisystem/01-nested_systems.01-two_levels.inp
- multisystem/01-nested_systems.02-three_levels.inp
- multisystem/01-nested_systems.03-four_levels.inp
- multisystem/03-interactions_creation.01-case1.inp
- multisystem/03-interactions_creation.02-case2.inp
- multisystem/03-interactions_creation.03-case3.inp
- multisystem/03-interactions_creation.04-case4.inp
- multisystem/04-propagation_verlet.01-two_body.inp
- multisystem/04-propagation_verlet.02-three_body.inp
- multisystem/05-propagation_beeman.01-two_body.inp
- multisystem/05-propagation_beeman.02-three_body.inp
- multisystem/06-propagation_expmid.01-two_body.inp
- multisystem/06-propagation_expmid.02-three_body.inp
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- multisystem/11-dftbplus_ehrenfest.01-benzene.inp
- multisystem/12-electronic_subsystem_propagators.02-expmid.inp
- multisystem/99-carbon_hydrogen.02-td.inp
- multisystem/99-carbon_hydrogen.03-td_restart.inp
- optimal_control/01-asym_doublewell.03-oct_run.inp
- optimal_control/01-asym_doublewell.04-oct_run.inp
- optimal_control/01-asym_doublewell.05-oct_run.inp
- optimal_control/02-sym_doublewell.03-oct.inp
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- optimal_control/08-velocities.01-ground_state.inp
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