From 482f4e8cbee50376d4624f9e4531c392db62b0d3 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Nyberg=20Borrfors?= Date: Mon, 23 Mar 2026 16:44:07 +0100 Subject: [PATCH] update RTP/EMD docs (#4990) --- docs/methods/sampling/ehrenfest.md | 42 +++++++++++++++--------------- 1 file changed, 21 insertions(+), 21 deletions(-) diff --git a/docs/methods/sampling/ehrenfest.md b/docs/methods/sampling/ehrenfest.md index dedc0510b3..aca7a8fc8f 100644 --- a/docs/methods/sampling/ehrenfest.md +++ b/docs/methods/sampling/ehrenfest.md @@ -249,7 +249,6 @@ RTP.inp is the input file used for such simulation: FILENAME =applied_field &END FIELD &PROJECTION_MO - REFERENCE_TYPE SCF REF_MO_FILE_NAME RTP-RESTART.wfn REF_MO_INDEX -1 SUM_ON_ALL_REF .FALSE. @@ -262,7 +261,6 @@ RTP.inp is the input file used for such simulation: &END PRINT &END PROJECTION_MO &PROJECTION_MO - REFERENCE_TYPE XAS_TDP REF_MO_FILE_NAME ${EXC_STATE_1} TD_MO_INDEX -1 SUM_ON_ALL_TD .FALSE. @@ -273,7 +271,6 @@ RTP.inp is the input file used for such simulation: &END PRINT &END PROJECTION_MO &PROJECTION_MO - REFERENCE_TYPE XAS_TDP REF_MO_FILE_NAME ${EXC_STATE_2} TD_MO_INDEX -1 SUM_ON_ALL_TD .FALSE. @@ -387,18 +384,18 @@ Note that the smaller this threshold, the more iterations per time step will be Hence, we have set the maximal iteration number [MAX_ITER](#CP2K_INPUT.FORCE_EVAL.DFT.REAL_TIME_PROPAGATION.MAX_ITER) at quite high value of 100. The time step used is rather small since we have to describe a core-hole excitation process that -takes place with a typical frequency of 529 eV. Following the rule of thumb to set the time step to -about 10 times the field frequency, we set [TIMESTEP](#CP2K_INPUT.MOTION.MD.TIMESTEP) to +takes place with a typical frequency of 529 eV. Following the rule of thumb to use a time step 10 +times smaller than the field wavelength, we set [TIMESTEP](#CP2K_INPUT.MOTION.MD.TIMESTEP) to `[fs] 0.00078` ### Field parameters The field is defined by its envelope, its intensity, its polarization along the laboratory x, y, and z-axis, its wavelength, and the original phase. Several types of field envelopes can be used. Here -we use a Gaussian one with a width of $\sigma=0.3073$ fs and centered at $T0=1.3190$ fs. The -intensity used is 4.08E+13 W.cm$^{-2}$. Along with a carrying frequency of 529 eV (approximately -2.34374655955 nm), it should promote about $10^{-3}$ from the Oxygen 1s to the first available -excited state. +we use a Gaussian with a width of $\sigma=0.3073$ fs and centered at $T0=1.3190$ fs. The intensity +used is 4.08E+13 W.cm$^{-2}$. Along with a carrying frequency of 529 eV (approximately 2.34374655955 +nm), it should promote about $10^{-3}$ electrons from the Oxygen 1s to the first available excited +state. ```none &EFIELD @@ -429,7 +426,6 @@ First, let us have a look at the projection toward the ground state: ```none &PROJECTION_MO - REFERENCE_TYPE SCF REF_MO_FILE_NAME RTP-RESTART.wfn REF_MO_INDEX -1 SUM_ON_ALL_REF .FALSE. @@ -450,10 +446,10 @@ All the time-dependent Molecular Orbitals are projected by setting to `.FALSE.`. This calculation is spin-independent so one does not have to define the spin of the MO to project. -The reference to projected to is loaded from the file `RTP-RESTART.wfn`, which is the ground state -obtained after the SCF cycles. Note that you can define a wave-function that is not the ground state -as long as the wave-function description (basis set, number of electrons...) is the same as the one -used for the real-time propagation. The `REFERENCE_TYPE` defaults to `SCF`. +The reference to project onto is loaded from the file `RTP-RESTART.wfn`, which is the ground state +obtained from the SCF calculation. Note that you can define a wave-function that is not the ground +state as long as the wave-function description (basis set, number of electrons...) is the same as +the one used for the real-time propagation. All the molecular orbitals available in this reference wave-function will be used as a reference for the projection by setting @@ -476,7 +472,6 @@ excited-states: ```none &PROJECTION_MO - REFERENCE_TYPE XAS_TDP REF_MO_FILE_NAME ${EXC_STATE_1} TD_MO_INDEX -1 SUM_ON_ALL_TD .FALSE. @@ -489,12 +484,17 @@ excited-states: ``` In this case, all the time-dependent MO are involved in the projection and stored separately. This -time, the reference wave function is supposed to be from an XAS_TDP calculation, see Linear Response -input file in the -[tutorial archive](https://github.com/cp2k/cp2k-examples/tree/master/rtp_field_xas). Running with -the proper parameters, this XAS_TDP run saves one .wfn file per excited state. Using -`REFERENCE_TYPE XAS_TDP`, the projection uses automatically the state saved in the produced wave -function file as the reference: +time, the reference wave function is obtained from an XAS_TDP calculation, see the +[RESTART_WFN](https://manual.cp2k.org/trunk/CP2K_INPUT/FORCE_EVAL/DFT/XAS_TDP/PRINT/RESTART_WFN.html) +option of the XAS_TDP module in the CP2K input reference. When requesting to print an excited state +wavefunction, the resulting .wfn file is that of the groundstate wavefunction except that the +initial orbital from which the electron is excited is replaced by the final orbital where the +electron is excited to. Therefore, please be aware that the ordering of the orbitals will affect +which file the excited orbital is written to. This is especially important to look out for if the +initial orbital is not of the lowest energy. + +XAS_TDP will save one .wfn file per printed excited state, and the projection during RTP is obtained +by: $$ n_{\omega}^i(t) = |<\omega | \psi_i(t)>|^2 = |\sum_{ab} \left( C_\omega^a \right)^* c_i^b(t) S_{ab} |^2