field
Specify an applied external field.
- Input block
Extended variant
field:
model: [formatted-string]
amplitude: [real]
direction: [x] [y] [z]
none
field:
model: delta
amplitude: 5.0e-3
direction: 1.0 0.0 0.0
mowindow
Enable the selective perturbation (SP) approach introduced in Kadek et al. PCCP 17, 22566 (2015). SP enables to represent the perturbation and response operators only in selected molecular orbitals, allowing thus to address a specific spectral region in RT-TDSCF simulations, as well as to eliminate nonphysical excitations that are artifacts of the finite basis representation. This keyword is very important for core-level spectroscopies.
- Input block
Extended variant
mowindow:
occupied: [intial-mo-index] - [final-mo-index]
virtual: [intial-mo-index] - [final-mo-index]
none
mowindow:
occupied: 4-6
mowindow:
occupied: 7-10
virtual: 15-46
Note
- By default, the entire orbital spectrum is considered.
- Occupied and virtual orbitals must be within their respective range. The range for occupied orbitals is from 1 to HOMO, whereas the range for virtual orbitals is from HOMO+1 to the total number of MOs.
Tip
- SP turns out to be particularly useful for X-ray spectroscopies, where excitations occur only from specific core-shell orbitals. Here, we recommed to select for perturbation only the core-shell occupied MOs.
analysis
Enable the transition density matrix analysis (TDMA) introduced in Repisky et al. JCTC 11, 980 (2015). TDMA enables to perform the orbital analysis of spectral transitions in RT-TDSCF simulations.
- Input block
Extended variant
analysis:
occupied: [intial-mo-index] - [final-mo-index]
virtual: [intial-mo-index] - [final-mo-index]
threshold: [real]
none
analysis:
occupied: 8-10
virtual: 11-25
threshold: 1.0e-5
Note
- By default, TDMA is disabled.
- Occupied and virtual orbitals must be within their respective range. The range for occupied orbitals is from 1 to HOMO, whereas the range for virtual orbitals is from HOMO+1 to the total number of MOs.
Tip
- Since TDMA may lead to an extensive data printout, we recommend to select only those orbitals relevant for the spectroscopy of interest.
time-steps
Define the time propagation details.
- Input line
- Default
time-steps:
[number-time-steps] x [time-step-length]
none
time-steps: 5000 x 0.05
maxiterations
Define the maximum number of micro-iterations (per time step) for the Magnus solver.
- Input line
- Default
maxiterations:
[integer]
maxiterations: 8
maxiterations: 5
Warning
- This keyword is relevant only for the Magnus solver, i.e. if the keyword "solver: magnus" is used. In addition, we recommend to setup the simulation time step such that the maximum number of micro-iterations does no exceed 5.
convergence
Define the convergence threshold for the Magnus solver.
- Input line
- Default
convergence:
[real]
convergence: 1.0e-07
convergence: 1.0e-5
Warning
- This keyword is relevant only for the Magnus solver, i.e. if the keyword "solver:magnus" is used.
checkpoint
Define the frequency of data checkpointing during the time propagation.
- Input line
- Default
checkpoint:
[integer]
checkpoint: 100
checkpoint: 500
x2c-transformation
Specify if one-electron operators are X2C picture-change transformed.
- Input line
- Default
x2c-transformation:
[string]
x2c-transformation: on
x2c-transformation: off
Warning
- This keyword is relevant only for the X2C-type Hamiltonians.
Latest Publications
Relativistic attosecond time-resolved XAS in ReSpect (J.Phys.Chem.Lett)
Accurate XAS spectra with new (e)amfX2C Hamiltonians (J.Phys.Chem.A)
Useful Links
Our Contacts
Department of Chemistry
UiT The Arctic University of Norway
Tromsø, NO-9037 Norway
Email: info@respectprogram.eu