Simulating Pump–Probe Photoelectron and Absorption Spectroscopy on the Attosecond Timescale with Time‐Dependent Density Functional Theory

Giovannini, Umberto De; Brunetto, Gustavo; Castro, Alberto; Walkenhorst, Jessica; Rubio, Ángel

doi:10.1002/cphc.201201007

Cited by 108 publications

(132 citation statements)

References 54 publications

Supporting

Mentioning

123

Contrasting

Order By: Relevance

“…For an idempotent density matrix in a molecular orbital basis ′ −′ = P P 0 2 (9) where 0 is a zero matrix and P′ = ′ P 1 2 . To quantify the deviation from idempotency of the excited state density matrices used in (10) where N is the number of basis functions.…”

Section: A Deviation From Idempotencymentioning

confidence: 99%

See 1 more Smart Citation

Excited State Absorption from Real-Time Time-Dependent Density Functional Theory

Fischer

Cramer

Govind

2015

J. Chem. Theory Comput.

View full text Add to dashboard Cite

The optical response of excited states is a key property used to probe photophysical and photochemical dynamics. Additionally, materials with a large nonlinear absorption cross-section caused by two-photon (TPA) and excited state absorption (ESA) are desirable for optical limiting applications. The ability to predict the optical response of excited states would help in the interpretation of transient absorption experiments and aid in the search for and design of optical limiting materials. We have developed an approach to obtain excited state absorption spectra by combining real-time (RT) and linear-response (LR) time-dependent density functional theory (TDDFT). Being based on RT-TDDFT, our method is aimed at tackling larger molecular complexes and materials systems where excited state absorption is predominantly seen and many time-resolved experimental efforts are focused. To demonstrate our method, we have calculated the ground and excited state spectra of H₂⁺ and H₂ due to the simplicity in the interpretation of the spectra. We have validated our new approach by comparing our results for butadiene with previously published results based on quadratic response (QR). We also present results for oligofluorenes, where we compare our results with both QR-TDDFT and experimental measurements. Because our method directly measures the response of an excited state, stimulated emission features are also captured; although, these features are underestimated in energy which could be attributed to a change of the reference from the ground to the excited state.

show abstract

Section: A Deviation From Idempotencymentioning

confidence: 99%

“…De Giovannini et al 9 have proposed a simulation protocol based on RT-TDDFT that is a direct simulation of a pump/probe experiment. One electric field is applied to excite the system to the state of interest, and then a second field is used to probe the response of the excited density.…”

Section: Introductionmentioning

confidence: 99%

Excited State Absorption from Real-Time Time-Dependent Density Functional Theory

Fischer

Cramer

Govind

2015

J. Chem. Theory Comput.

View full text Add to dashboard Cite

show abstract

“…Rozzi et al have used RT‐TDDFT to identify the important role of quantum (de)coherence in controlling the rate of charge separation in an artificial light‐harvesting system . RT‐TDDFT has also been used to simulate time‐resolved “pump‐probe” spectroscopy of the helium atom and ethylene molecule …”

Section: Overview Of Applicationsmentioning

confidence: 99%

Electron dynamics with real‐time time‐dependent density functional theory

Provorse

Isborn

2016

Int J of Quantum Chemistry

129

116

View full text Add to dashboard Cite

Real-time time-dependent functional theory (RT-TDDFT) directly propagates the electron density in the time domain by integrating the time-dependent Kohn-Sham equations. This is in contrast to the popular linear response TDDFT matrix formulation that computes transition frequencies from a ground state reference. RT-TDDFT is, therefore, a potentially powerful technique for modeling atto-to picosecond electron dynamics, including charge transfer pathways, the response to a specific applied field, and frequency dependent linear and nonlinear properties. However, qualitatively incorrect electron dynamics and time-dependent resonant frequencies can occur when perturbing the density away from the ground state due to the common adiabatic approximation. An overview of the RT-TDDFT method is provided here, including examples of some cases that lead to this qualitatively incorrect behavior.

show abstract

“…The latter is done by applying a delta-kick [51] right after the laser is turned off, followed by a free evolution of some duration T and then Fourier transforming the ensuing dipole difference between the kicked and un-kicked free propagations [22,29,30] …”

Section: A Charge Transfer From a Photoexcited Statementioning

confidence: 99%

Studies of spuriously shifting resonances in time-dependent density functional theory

Luo

Fuks

Maitra

2016

The Journal of Chemical Physics

View full text Add to dashboard Cite

Adiabatic approximations in time-dependent density functional theory (TDDFT) will in general yield unphysical time-dependent shifts in the resonance positions of a system driven far from its ground-state. This spurious time-dependence is explained in [J. I. Fuks, K. Luo, E. D. Sandoval and N. T. Maitra, Phys. Rev. Lett. 114, 183002 (2015)] in terms of the violation of an exact condition by the non-equilibrium exchange-correlation kernel of TDDFT. Here we give details on the derivation and discuss reformulations of the exact condition that apply in special cases. In its most general form, the condition states that when a system is left in an arbitrary state, the TDDFT resonance position for a given transition in the absence of time-dependent external fields and ionic motion, is independent of the state. Special cases include the invariance of TDDFT resonances computed with respect to any reference interacting stationary state of a fixed potential, and with respect to any choice of appropriate stationary Kohn-Sham reference state. We then present several case studies, including one that utilizes the adiabatically-exact approximation, that illustrate the conditions and the impact of their violation on the accuracy of the ensuing dynamics. In particular, charge-transfer across a long-range molecule is hampered, and we show how adjusting the frequency of a driving field to match the time-dependent shift in the charge-transfer resonance frequency, results in a larger charge transfer over time.

show abstract

Simulating Pump–Probe Photoelectron and Absorption Spectroscopy on the Attosecond Timescale with Time‐Dependent Density Functional Theory

Cited by 108 publications

References 54 publications

Excited State Absorption from Real-Time Time-Dependent Density Functional Theory

Excited State Absorption from Real-Time Time-Dependent Density Functional Theory

Electron dynamics with real‐time time‐dependent density functional theory

Studies of spuriously shifting resonances in time-dependent density functional theory

Contact Info

Product

Resources

About