Nonadiabatic dynamics simulations on internal conversion and intersystem crossing processes in gold(i) compounds

A highly efficient protocol for performing nonadiabatic dynamics simulations is implemented and applied to ultrafast internal conversion and intersystem crossing in various molecules.

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Internal conversion and intersystem crossing in α,β-enones: a combination of electronic structure calculations and dynamics simulations

Physical Chemistry Chemical Physics ◽

10.1039/c5cp06833a ◽

2016 ◽

Vol 18 (9) ◽

pp. 6931-6945 ◽

Cited By ~ 10

Author(s):

Jun Cao ◽

Zhi-Zhong Xie

Keyword(s):

Electronic Structure ◽

Internal Conversion ◽

Electronic Structure Calculations ◽

Intersystem Crossing ◽

Geometrical Constraint ◽

Spin Orbital ◽

Dynamics Simulations ◽

Structure Calculations ◽

Spin Orbital Coupling

The geometrical constraint of the ring gives rise to a smaller spin–orbital coupling in the singlet–triplet crossing region, resulting in a lower intersystem crossing rate.

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Ultrafast intersystem crossing in xanthone from wavepacket dynamics simulations

10.33774/chemrxiv-2021-k6hqt-v2 ◽

2021 ◽

Author(s):

Marc Alías Rodríguez ◽

Coen De Graaf ◽

Miquel Huix-Rotllant

Keyword(s):

Gas Phase ◽

Internal Conversion ◽

Minimum Energy ◽

Dynamics Simulation ◽

Intersystem Crossing ◽

Singlet Excited State ◽

Radiationless Transition ◽

Wavepacket Dynamics ◽

Dynamics Simulations ◽

Triplet Transition

Most aromatic ketones containing first-row elements undergo unexpectedly fast intersystem crossing in few tens of picosecond and a quantum yield close to unity. Among them, xanthone (9H-xanthen-9-one) possesses one of the fastest intersystem crossing rates of ~1.5 ps, despite containing only first-row elements. The exact mechanism of this unusually fast singlet-triplet transition is still under debate. Here, we perform a complete wavepacket dynamics simulation of the internal conversion and intersystem crossing reactions of xanthone in the gas phase. We show that xanthone follows El-Sayed's rule for intersystem crossing. From the second singlet excited state, the mechanism is sequential: (i) an internal conversion between singlets 1pipi*-1npi* (~0.14 fs), (ii) an intersystem crossing 1npi*-3pipi* (~1.8 ps), and (iii) an internal conversion between triplets 3pipi*-3npi* (~27 ps). Each transfer finds its origin in a barrierless access to electronic state intersections. These intersections are close to minimum energy structures, allowing for an efficient radiationless transition from 1pipi* to 3npi*.

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Nonadiabatic Dynamics Simulation of Photoinduced Ring-Opening Reaction of 2(5H)-Thiophenone with Internal Conversion and Intersystem Crossing

Physical Chemistry Chemical Physics ◽

10.1039/d1cp00281c ◽

2021 ◽

Author(s):

Bin-Bin Xie ◽

Bo Long Liu ◽

Xiu-Fang Tang ◽

Diandong Tang ◽

Lin Shen ◽

...

Keyword(s):

Ring Opening ◽

Internal Conversion ◽

Mean Field ◽

Dynamics Simulation ◽

Quantum Trajectory ◽

Intersystem Crossing ◽

Nonadiabatic Dynamics ◽

Field Approach ◽

Ring Opening Reaction

In the present work, the quantum trajectory mean-field approach, which is able to overcome the overcoherence problem, was generalized to simulate internal conversion and intersystem crossing processes simultaneously. The photoinduced...

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Intersystem crossing quantum yield of quinoxaline; evidence for high yield of internal conversion of the first excited singlet state to the ground state

Chemical Physics Letters ◽

10.1016/0009-2614(70)85219-8 ◽

1970 ◽

Vol 6 (5) ◽

pp. 549-550 ◽

Cited By ~ 8

Author(s):

Steven G. Hadley

Keyword(s):

Quantum Yield ◽

Ground State ◽

Internal Conversion ◽

Singlet State ◽

Excited Singlet State ◽

High Yield ◽

Intersystem Crossing ◽

Excited Singlet

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X-ray transient absorption reveals the 1Au (nπ*) state of pyrazine in electronic relaxation

Nature Communications ◽

10.1038/s41467-021-25045-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Valeriu Scutelnic ◽

Shota Tsuru ◽

Mátyás Pápai ◽

Zheyue Yang ◽

Michael Epshtein ◽

...

Keyword(s):

Electronic Excitation ◽

Transient Absorption ◽

Transient Absorption Spectroscopy ◽

Electronic Relaxation ◽

Nonadiabatic Dynamics ◽

X Ray ◽

Organic Chromophores ◽

Dynamics Simulations ◽

X Ray Absorption ◽

Structure Calculations

AbstractElectronic relaxation in organic chromophores often proceeds via states not directly accessible by photoexcitation. We report on the photoinduced dynamics of pyrazine that involves such states, excited by a 267 nm laser and probed with X-ray transient absorption spectroscopy in a table-top setup. In addition to the previously characterized 1B2u (ππ*) (S2) and 1B3u (nπ*) (S1) states, the participation of the optically dark 1Au (nπ*) state is assigned by a combination of experimental X-ray core-to-valence spectroscopy, electronic structure calculations, nonadiabatic dynamics simulations, and X-ray spectral computations. Despite 1Au (nπ*) and 1B3u (nπ*) states having similar energies at relaxed geometry, their X-ray absorption spectra differ largely in transition energy and oscillator strength. The 1Au (nπ*) state is populated in 200 ± 50 femtoseconds after electronic excitation and plays a key role in the relaxation of pyrazine to the ground state.

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