Time-dependent configuration-interaction calculations of laser-pulse-driven many-electron dynamics: Controlled dipole switching in lithium cyanide

Femtosecond electron dynamics based on time-dependent configuration interaction (TDCI) is a numerically rigorous approach for quantitative modeling of electron-injection across molecular junctions. Our simulations of cyanobenzene thiolates---para- and meta-linked to an acceptor gold atom---corroborate aromatic resonance stabilization effects and show donor states \emph{conjugating} with the benzene $\pi$-network to exhibit superior electron-injection dynamics across the para-linked isomer compared to the meta counterpart. For a \emph{non-conjugating} initial state, we find electron-injection through the meta-channel to stem from non-resonant quantum mechanical tunneling. Furthermore, we demonstrate quantum interference to drive para- vs. meta- selectivity in the coherent evolution of superposed $\pi$(CN)- and $\sigma$(NC-C)-type wavepackets. Analyses reveal that in the para-linked molecule, $\sigma$, and $\pi$ MOs localized at the donor terminal are \emph{in-phase} leading to constructive interference of electron density distribution while phase-flip of one of the MOs in the meta-linked molecule results in destructive interference. The findings reported here suggest that \emph{a priori} detection of orbital phase-flip and quantum coherence conditions can aid in molecular device design strategies.

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Charge-transfer selectivity and quantum interference in real-time electron dynamics: Gaining insights from time-dependent configuration interaction simulations

The Journal of Chemical Physics ◽

10.1063/5.0009196 ◽

2020 ◽

Vol 152 (19) ◽

pp. 194111 ◽

Cited By ~ 2

Author(s):

Raghunathan Ramakrishnan

Keyword(s):

Charge Transfer ◽

Real Time ◽

Configuration Interaction ◽

Quantum Interference ◽

Time Dependent ◽

Electron Dynamics

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EFFECT OF ELECTRON CORRELATION ON THE TWO-PARTICLE DYNAMICS OF A HELIUM ATOM IN A STRONG LASER PULSE

International Journal of Modern Physics B ◽

10.1142/s0217979202007987 ◽

2002 ◽

Vol 16 (03) ◽

pp. 415-452 ◽

Cited By ~ 5

Author(s):

NILS ERIK DAHLEN

Keyword(s):

Laser Pulse ◽

Helium Atom ◽

Electron Correlation ◽

Density Functional ◽

Femtosecond Laser Pulses ◽

Time Dependent ◽

Electron Dynamics ◽

Dimensional Model ◽

One Dimensional ◽

Hartree Fock

This review discusses the complicated two-electron dynamics of a helium atom in an intense, short laser pulse. A helium gas in femtosecond laser pulses at long wave lengths (λ~700 nm) and high intensities (I~1015 W /cm2) produces surprisingly high numbers of He2+ ions. These laser fields cause large and fast electron oscillations, which makes a solution of the time-dependent Schrödinger equation numerically demanding. The system can be studied using a one-dimensional model atom, which has many of the same properties as the He atom. Using the one-dimensional model, the importance of including electron correlation in a simplified description of the two-electron dynamics is demonstrated. It is shown that electron correlation becomes much less important if the laser field has a short wave length, in which case the electron oscillations are smaller and slower. The problem of including electron correlation in the calculations is discussed in terms of approaches such as time-dependent Hartree–Fock, time-dependent density functional theory and time-dependent extended Hartree–Fock. Some of the commonly used semi-classical models for describing the double-ionization process are presented.

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Simulating Electron Dynamics of Complex Molecules with Time-Dependent Complete Active Space Configuration Interaction

Journal of Chemical Theory and Computation ◽

10.1021/acs.jctc.8b00381 ◽

2018 ◽

Vol 14 (8) ◽

pp. 4129-4138 ◽

Cited By ~ 13

Author(s):

Wei-Tao Peng ◽

B. Scott Fales ◽

Benjamin G. Levine

Keyword(s):

Configuration Interaction ◽

Time Dependent ◽

Electron Dynamics ◽

Complex Molecules ◽

Complete Active Space ◽

Active Space

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Laser-induced electron dynamics including photoionization: A heuristic model within time-dependent configuration interaction theory

The Journal of Chemical Physics ◽

10.1063/1.3218847 ◽

2009 ◽

Vol 131 (11) ◽

pp. 114304 ◽

Cited By ~ 43

Author(s):

Stefan Klinkusch ◽

Peter Saalfrank ◽

Tillmann Klamroth

Keyword(s):

Configuration Interaction ◽

Time Dependent ◽

Heuristic Model ◽

Interaction Theory ◽

Electron Dynamics

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Quantum Interference in Real-Time Electron-Dynamics: Gaining Insights from Time-Dependent Configuration Interaction Simulations

10.26434/chemrxiv.11086292.v1 ◽

2019 ◽

Author(s):

Raghunathan Ramakrishnan

Keyword(s):

Configuration Interaction ◽

Quantum Interference ◽

Quantum Coherence ◽

Gold Atom ◽

Electron Injection ◽

Time Dependent ◽

Destructive Interference ◽

Electron Dynamics ◽

Initial State ◽

Donor States

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #000000; background-color: #ffffc9} span.s1 {font-variant-ligatures: no-common-ligatures} span.s2 {font-variant-ligatures: no-common-ligatures; color: #2cb11b} span.s3 {font-variant-ligatures: no-common-ligatures; color: #c611c6} span.s4 {font-variant-ligatures: no-common-ligatures; color: #be631a} Femtosecond electron dynamics based on time-dependent configuration interaction (TDCI) is a numerically rigorous approach for quantitative modeling of electron-injection across molecular junctions. Our simulations of cyanobenzene thiolates---para- and meta-linked to an acceptor gold atom---corroborate aromatic resonance stabilization effects and show donor states \emph{conjugating} with the benzene $\pi$-network to exhibit superior electron-injection dynamics across the para-linked isomer compared to the meta counterpart. For a \emph{non-conjugating} initial state, we find electron-injection through the meta-channel to stem from non-resonant quantum mechanical tunneling. Furthermore, we demonstrate quantum interference to drive para- vs. meta- selectivity in the coherent evolution of superposed $\pi$(CN)- and $\sigma$(NC-C)-type wavepackets. Analyses reveal that in the para-linked molecule, $\sigma$, and $\pi$ MOs localized at the donor terminal are \emph{in-phase} leading to constructive interference of electron density distribution while phase-flip of one of the MOs in the meta-linked molecule results in destructive interference. The findings reported here suggest that \emph{a priori} detection of orbital phase-flip and quantum coherence conditions can aid in molecular device design strategies.

Download Full-text