ESR and Electronic Relaxation of Cr3+ and Fe3+ in Water and Water–Glycerol Mixtures

Abstract Dynamic Nuclear Polarization (DNP) studies of TANOL/water-glycerol solutions were per-formed at 1.53 mT. The samples have either various water-glycerol ratios at constant concentration or various concentrations at a constant water-glycerol ratio. The low field EPR spectra were recorded, the DNP parameters(enhancement factors, coupling constant, leakage factor) were determined, electronic relaxation times were measured. Depending on the values obtained, the interactions between nuclei and electrons are discussed.

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ELECTRONIC RELAXATION IN RARE EARTH METALS AND ALLOYS - A NON-KRAMERS EXAMPLE : Tm3+

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1980104 ◽

1980 ◽

Vol 41 (C1) ◽

pp. C1-25-C1-31 ◽

Cited By ~ 1

Author(s):

N. S. Dixon ◽

L. S. Fritz ◽

Y. Mahmud ◽

B. B. Triplett ◽

S. S. Hanna ◽

...

Keyword(s):

Rare Earth ◽

Rare Earth Metals ◽

Metals And Alloys ◽

Electronic Relaxation

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Inverse electronic relaxation in the case of multiphoton excitation of molecules by infrared laser radiation

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0157.198901b.0051 ◽

1989 ◽

Vol 157 (1) ◽

pp. 51 ◽

Cited By ~ 3

Author(s):

A.A. Puretskii ◽

V.V. Tyakht

Keyword(s):

Laser Radiation ◽

Infrared Laser ◽

Electronic Relaxation ◽

Multiphoton Excitation

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Excited-State Dynamics in the RNA Nucleotide Uridine 5’-Monophosphate Investigated by Femtosecond Broadband Transient Absorption Spectroscopy

10.26434/chemrxiv.7860023 ◽

2019 ◽

Author(s):

Matthew M. Brister ◽

Carlos Crespo-Hernández

Keyword(s):

Excited State ◽

Excited States ◽

Ground State ◽

Transient Absorption ◽

Electronic Energy ◽

Transient Absorption Spectroscopy ◽

Electronic Relaxation ◽

Vibrationally Excited ◽

Excited State Dynamics ◽

Π State

Damage to RNA from ultraviolet radiation induce chemical modifications to the nucleobases. Unraveling the excited states involved in these reactions is essential, but investigations aimed at understanding the electronic-energy relaxation pathways of the RNA nucleotide uridine 5’-monophosphate (UMP) have not received enough attention. In this Letter, the excited-state dynamics of UMP is investigated in aqueous solution. Excitation at 267 nm results in a trifurcation event that leads to the simultaneous population of the vibrationally-excited ground state, a longlived 1nOπ* state, and a receiver triplet state within 200 fs. The receiver state internally convert to the long-lived 3ππ* state in an ultrafast time scale. The results elucidate the electronic relaxation pathways and clarify earlier transient absorption experiments performed for uracil derivatives in solution. This mechanistic information is important because long-lived nπ* and ππ* excited states of both singlet and triplet multiplicities are thought to lead to the formation of harmful photoproducts.

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The 1,2-propanediol-sensing properties of one-dimension Tb2O3-modified ZnO nanowires synthesized by water-glycerol binary thermal route

Analytica Chimica Acta ◽

10.1016/j.aca.2021.338454 ◽

2021 ◽

Vol 1160 ◽

pp. 338454

Author(s):

Wanyi Ling ◽

Wang Jian ◽

Niu Gao ◽

Dachuan Zhu

Keyword(s):

Zno Nanowires ◽

One Dimension ◽

Sensing Properties ◽

Water Glycerol

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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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