pathak_2022#
H. Pathak, T. Sato and K. L. Ishikawa, “Time-dependent optimized coupled-cluster method with doubles and perturbative triples for first principles simulation of multielectron dynamics”, Front. Chem. 10, 982120 (2022)
Source record · Catalogue · Review register
DOI: 10.3389/fchem.2022.982120
Source kind: theory
Recorded technique: Time-dependent many-electron calculations of Kr in a laser pulse (Sec. 3, PDF p. 4): TDHF, TD-OCCD (time-dependent optimised coupled-cluster doubles), TD-OCCD(T) (with perturbative triples, introduced here) and TD-CASSCF; the dipole interaction V_ext = A(t) p_z ‘in the velocity gauge’, A(t) = -int^t E(t’) dt’, the field ‘linearly polarized along the z axis’ (Sec. 2). ‘In all correlation calculations, eight electrons of 4s4p orbitals are considered as active and correlated among thirteen active orbitals’; whether the 28 core electrons are frozen or dynamical, and TDHF’s number of orbitals, are not stated. Orbitals on a spherical FEDVR basis: l_max = 72, 0 < r < 300 with 78 finite elements of 25 DVR functions each, a cos^(1/4) mask switched on at r = 180; fourth-order exponential Runge-Kutta, 20 000 time steps per optical cycle; ‘We run the simulations for a further 6,000 time steps after the end of the pulse’ (Table 2’s note: ‘66000 time steps (0 <= t <= 3.3T)’). The pulse: ‘a three-cycle laser pulse with a central wavelength of 800 nm having intensity 2 x 10^14 W/cm2 and a period of T = 2 pi / omega_0 ~ 2.67 fs’; its envelope and carrier phase are not stated. The single-ionisation probability: ‘we computed the probability of finding an electron outside a sphere of a radius of 20 a.u. using RDMs defined in Refs. 19; 20; 37’ (p. 4).
Materials in structured entries: Kr
Dataset quantities: ionization_yield
Contents: 4 datasets; 0 formulas.
Curation notes#
PDF pages 1-7 (Frontiers’ layout). Identity checked on the first page (2026-10-06): ‘Time-dependent optimized coupled-cluster method with doubles and perturbative triples for first principles simulation of multielectron dynamics’, Himadri Pathak, Takeshi Sato and Kenichi L. Ishikawa (The University of Tokyo), Front. Chem. 10:982120, doi 10.3389/fchem.2022.982120, received 30 June 2022, accepted 09 August 2022, published 13 September 2022.
EXTRACTED (tools/extract/pathak_2022.py). The paper prints no number of the time-dependent calculations: the single-ionisation probabilities are only in Fig. 2 (PDF p. 4), an image embedded in the PDF (927 x 642 pixels, JPEG, 300 dpi; its tick labels are part of the image, not text), read from its native pixels by data rule 8 (TC-699). The data availability statement (p. 5): ‘The raw data supporting the conclusion of this article will be made available by the authors, without undue reservation’; they have not been asked, and the numbers here would be replaced by theirs. Axes calibrated from the frame lines and the inward tick marks, their darkness-weighted centres written in the script and found again in the image (each within 0.25 pixel; the left and right marks agree within 0.25 pixel): time 1.0 to 3.0 optical cycles (395.7 pixels per cycle), probability 0.0000 to 0.1200 (92.74 pixels per 0.02; 2.16e-4 per pixel), linear; the worst tick residuals 0.03 pixel (x) and 0.06 pixel (y). Each curve is picked by its colour as the legend shows (TD-CASSCF red, TD-OCCD(T) black, TD-OCCD green, TDHF blue; the legend’s order checked) and traced column by column from a seed at column 880 (2.93 cycles); its row is the colour’s weighted centre in the column. The lines are 3-4 pixels wide and do not overlap near the end (12 pixels apart at least).
THE TIME. The axis ends at 3.0 cycles = 3T (330.96 au), the end of the pulse, under the frame’s right line; the simulation ran on to 3.3T, which the figure does not show. The value is the traced row at column 905, 2.9939 cycles (0.7 au before 3T), the last clear of the frame’s line; a straight line through the rows of the last 20 columns, extrapolated to 3.0 cycles, agrees within 0.75 pixel (TD-OCCD(T), whose line wiggles there by about 1 pixel; the others within 0.2 pixel); both are in each printed cell. Unlike Pathak et al. 2020’s argon at 1200 nm, the curves are still rising at 3T: from 2.5 cycles to 3T, TDHF from 0.0828 to 0.0860, TD-CASSCF from 0.1154 to 0.1205 (4 %).
THE VALUES at 3T: TD-CASSCF 0.1205, TD-OCCD(T) 0.1177, TD-OCCD 0.1152, TDHF 0.08599 (0.977, 0.956 and 0.714 times TD-CASSCF). The checks (the script fails if one is missed): the order at 3T is the legend’s, as the text says (‘a substantial underestimation ... by the TDHF method’; ‘All correlation methods perform according to their ability to treat electron correlation’; TD-OCCDT, not shown, is ‘not identifiable from the TD-CASSCF results within the graphical resolution’); the TDHF line is at zero before the pulse ionises (1.04 to 1.24 cycles), drawn 1.5 pixels (3.2e-4) above the zero tick: the drawing’s own offset, not corrected. The traced rows, overlaid on the image enlarged eight times, follow the centre of every line from column 880 to the frame (inspected 2026-10-06).
DIGITISING UNCERTAINTY: one pixel is 2.16e-4 (0.18 % of TD-CASSCF, 0.25 % of TDHF); the line’s centre is found to about half a pixel, the extrapolation to 3T moves it by up to 0.75 pixel, and the zero of the drawing is 1.5 pixels off the tick: about 2.5 pixels in all, 0.45-0.63 %. 1 % is stated (the paper states none).
THE PULSE. ‘three-cycle’ is read as the total, foot-to-foot duration 3T = 8.005 fs (T = 2.6685 fs at 800 nm; the paper’s ‘~2.67 fs’), as in the group’s Pathak et al. 2020 (Eq. 29: E(t) = E0 sin(omega_0 t) sin^2(pi t / 3T) on the field). The sin^2 envelope on the field is assumed from that paper, not stated here; the carrier-envelope phase is not stated (cep = ‘not stated’). The abscissa is the stated peak intensity.
NOT TAKEN: Fig. 1 (the dipole moments), Fig. 3 (harmonic spectra), Table 1 (ground state energies), Table 2 (computation times).
Recorded bibliographic identity status: VALIDATED. This concerns identification of the source; it does not establish the scientific correctness of its contents.
Datasets#
pathak_2022/fig2_tdhf_Kr#
{
"id": "fig2_tdhf_Kr",
"material": "Kr",
"file": "Kr/pathak_2022__fig2_tdhf_Kr.csv",
"table": "fig_d7a5c6e5e701",
"digitised": "raster",
"quantity": "ionization_yield",
"unit": "1",
"abscissa": "intensity",
"abscissa_unit": "W/cm2",
"use": "check",
"uncertainty": {
"relative": 0.01,
"level": "not stated"
},
"parameters": {
"wavelength_nm": 800,
"pulse_fs": 8.005,
"pulse_fs_definition": "the total, foot-to-foot duration: 'a three-cycle laser pulse' (3 cycles foot to foot assumed, as in the group's Pathak et al. 2020)",
"polarization": "linear",
"pulse_envelope": "sin^2",
"envelope_of": "field (assumed: the paper does not state the envelope)",
"cep": "not stated",
"cep_definition": "not stated; the group's Pathak et al. 2020 Eq. 29, E(t) = E0 sin(omega t) sin^2(pi t / tau), 0 <= t <= tau, is the natural assumption",
"measure": "the probability of finding an electron outside a sphere of R0 = 20 a.u., at t = 3T (from the reduced density matrices)",
"method": "TDHF, velocity gauge, FEDVR l_max = 72, R_max = 300 au (the number of orbitals not stated)",
"electrons": "the eight 4s4p electrons active (the treatment of the 28 core electrons not stated)"
}
}
Fig. 2, p. 4, TDHF (blue): the single-ionisation probability of Kr, ‘the probability of finding an electron outside a sphere of a radius of 20 a.u.’, at the end of the pulse, t = 3T (the axis’s end), at 2e14 W/cm^2: 0.08599, read from the image (the record’s notes). 0.714 times TD-CASSCF. 1 %: the digitising (about 2.5 pixels, 0.6 %) rounded up; the paper states none (the record’s notes).
pathak_2022/fig2_tdoccd_Kr#
{
"id": "fig2_tdoccd_Kr",
"material": "Kr",
"file": "Kr/pathak_2022__fig2_tdoccd_Kr.csv",
"table": "fig_d7a5c6e5e701",
"digitised": "raster",
"quantity": "ionization_yield",
"unit": "1",
"abscissa": "intensity",
"abscissa_unit": "W/cm2",
"use": "check",
"uncertainty": {
"relative": 0.01,
"level": "not stated"
},
"parameters": {
"wavelength_nm": 800,
"pulse_fs": 8.005,
"pulse_fs_definition": "the total, foot-to-foot duration: 'a three-cycle laser pulse' (3 cycles foot to foot assumed, as in the group's Pathak et al. 2020)",
"polarization": "linear",
"pulse_envelope": "sin^2",
"envelope_of": "field (assumed: the paper does not state the envelope)",
"cep": "not stated",
"cep_definition": "not stated; the group's Pathak et al. 2020 Eq. 29, E(t) = E0 sin(omega t) sin^2(pi t / tau), 0 <= t <= tau, is the natural assumption",
"measure": "the probability of finding an electron outside a sphere of R0 = 20 a.u., at t = 3T (from the reduced density matrices)",
"method": "TD-OCCD (time-dependent optimised coupled-cluster doubles), velocity gauge, 13 active orbitals, FEDVR l_max = 72, R_max = 300 au",
"electrons": "the eight 4s4p electrons correlated in 13 active orbitals (the treatment of the 28 core electrons not stated)"
}
}
Fig. 2, p. 4, TD-OCCD (green): the single-ionisation probability of Kr, ‘the probability of finding an electron outside a sphere of a radius of 20 a.u.’, at the end of the pulse, t = 3T (the axis’s end), at 2e14 W/cm^2: 0.1152, read from the image (the record’s notes). 0.956 times TD-CASSCF. 1 %: the digitising (about 2.5 pixels, 0.5 %) rounded up; the paper states none (the record’s notes).
pathak_2022/fig2_tdoccdpt_Kr#
{
"id": "fig2_tdoccdpt_Kr",
"material": "Kr",
"file": "Kr/pathak_2022__fig2_tdoccdpt_Kr.csv",
"table": "fig_d7a5c6e5e701",
"digitised": "raster",
"quantity": "ionization_yield",
"unit": "1",
"abscissa": "intensity",
"abscissa_unit": "W/cm2",
"use": "check",
"uncertainty": {
"relative": 0.01,
"level": "not stated"
},
"parameters": {
"wavelength_nm": 800,
"pulse_fs": 8.005,
"pulse_fs_definition": "the total, foot-to-foot duration: 'a three-cycle laser pulse' (3 cycles foot to foot assumed, as in the group's Pathak et al. 2020)",
"polarization": "linear",
"pulse_envelope": "sin^2",
"envelope_of": "field (assumed: the paper does not state the envelope)",
"cep": "not stated",
"cep_definition": "not stated; the group's Pathak et al. 2020 Eq. 29, E(t) = E0 sin(omega t) sin^2(pi t / tau), 0 <= t <= tau, is the natural assumption",
"measure": "the probability of finding an electron outside a sphere of R0 = 20 a.u., at t = 3T (from the reduced density matrices)",
"method": "TD-OCCD(T) (time-dependent optimised coupled-cluster doubles with perturbative triples), velocity gauge, 13 active orbitals, FEDVR l_max = 72, R_max = 300 au",
"electrons": "the eight 4s4p electrons correlated in 13 active orbitals (the treatment of the 28 core electrons not stated)"
}
}
Fig. 2, p. 4, TD-OCCD(T) (black): the single-ionisation probability of Kr, ‘the probability of finding an electron outside a sphere of a radius of 20 a.u.’, at the end of the pulse, t = 3T (the axis’s end), at 2e14 W/cm^2: 0.1177, read from the image (the record’s notes). The paper’s new method; 0.977 times TD-CASSCF. 1 %: the digitising (about 2.5 pixels, 0.5 %) rounded up; the paper states none (the record’s notes).
pathak_2022/fig2_tdcasscf_Kr#
{
"id": "fig2_tdcasscf_Kr",
"material": "Kr",
"file": "Kr/pathak_2022__fig2_tdcasscf_Kr.csv",
"table": "fig_d7a5c6e5e701",
"digitised": "raster",
"quantity": "ionization_yield",
"unit": "1",
"abscissa": "intensity",
"abscissa_unit": "W/cm2",
"use": "check",
"uncertainty": {
"relative": 0.01,
"level": "not stated"
},
"parameters": {
"wavelength_nm": 800,
"pulse_fs": 8.005,
"pulse_fs_definition": "the total, foot-to-foot duration: 'a three-cycle laser pulse' (3 cycles foot to foot assumed, as in the group's Pathak et al. 2020)",
"polarization": "linear",
"pulse_envelope": "sin^2",
"envelope_of": "field (assumed: the paper does not state the envelope)",
"cep": "not stated",
"cep_definition": "not stated; the group's Pathak et al. 2020 Eq. 29, E(t) = E0 sin(omega t) sin^2(pi t / tau), 0 <= t <= tau, is the natural assumption",
"measure": "the probability of finding an electron outside a sphere of R0 = 20 a.u., at t = 3T (from the reduced density matrices)",
"method": "TD-CASSCF (time-dependent complete-active-space self-consistent field), velocity gauge, 13 active orbitals, FEDVR l_max = 72, R_max = 300 au",
"electrons": "the eight 4s4p electrons correlated in 13 active orbitals (the treatment of the 28 core electrons not stated)"
}
}
Fig. 2, p. 4, TD-CASSCF (red): the single-ionisation probability of Kr, ‘the probability of finding an electron outside a sphere of a radius of 20 a.u.’, at the end of the pulse, t = 3T (the axis’s end), at 2e14 W/cm^2: 0.1205, read from the image (the record’s notes). The benchmark within the active space. 1 %: the digitising (about 2.5 pixels, 0.45 %) rounded up; the paper states none (the record’s notes).
Formulas#
No formulas are recorded.
Corrections#
No dataset errata are recorded in this source record.
Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the review register for the checks and decisions.