A microsecond time resolved x-ray absorption near edge structure synchrotron study of phase transitions in Fe undergoing ramp heating at high pressure

Polarized time-resolved X-ray absorption near edge structure (XANES) is used to characterize the sequential ballistic excited state dynamics of two B12 vitamers: cyanocobalamin and adenosylcobalamin. Excitation at 550 nm and 365 nm is used to resolve axial and equatorial contributions to the excited state dynamics.

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Observation of pressure-induced electron transfer in SnC2O4

Physical Chemistry Chemical Physics ◽

10.1039/d1cp00306b ◽

2021 ◽

Author(s):

Michael Pravica ◽

Roman Chernikov ◽

Kevin Ayala Pineda ◽

Jianbao Zhao ◽

Petrika Cifligu ◽

...

Keyword(s):

High Pressure ◽

Electron Transfer ◽

Phase Transitions ◽

Absorption Spectroscopy ◽

Diamond Anvil Cell ◽

X Ray ◽

Pressure Behavior ◽

Diamond Anvil ◽

X Ray Absorption

We examined the high pressure behavior of stannous oxalate via Raman and x-ray absorption spectroscopy (XAS) inside a diamond anvil cell. Phase transitions were observed to occur near 2.6 and...

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Time-Resolved X-Ray Absorption of An Amorphous Si Foil During Pulsed Laser Irradiation

MRS Proceedings ◽

10.1557/proc-51-119 ◽

1985 ◽

Vol 51 ◽

Author(s):

Kouichi Murakami ◽

Hans C. Gerritsen ◽

Hedser Van Brug ◽

Fred Bijkerk ◽

Frans W. Saris ◽

...

Keyword(s):

Laser Irradiation ◽

Direct Evidence ◽

Pulsed Laser ◽

Time Resolved ◽

Edge Structure ◽

X Ray ◽

Nanosecond Pulsed Laser ◽

Amorphous Si ◽

X Ray Absorption ◽

Pulsed Laser Irradiation

ABSTRACTWe report time-resolved X-ray absorption and extended X-ray absorption fine structure (EXAFS) measurements on amorphous silicon under nanosecond pulsed-laser irradiation. Each measurement was performed with one laser shot in the X-ray energy range from 90 to 300 eV. An X-ray absorption spectrum for induced liquid Si (liq*Si) was first observed above an energy density of 0.17 J/cm2. It differs significantly from the spectrum for amorphous Si and characteristically shows the disappearance of the Si-L(II,III) edge structure at around 100 eV. This phenomenon is interpreted in terms of a significant reduction in the 3s-like character of the unfilled part of the conduction band of liq*Si compared to that of amorphous Si. This is the first direct evidence that liq*Si has a metallic-like electronic structure. Timeresolved EXAFS results are also discussed briefly.

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Time-resolved XAFS measurement using quick-scanning techniques at BSRF

Journal of Synchrotron Radiation ◽

10.1107/s1600577517005276 ◽

2017 ◽

Vol 24 (3) ◽

pp. 674-678 ◽

Cited By ~ 3

Author(s):

Shengqi Chu ◽

Lirong Zheng ◽

Pengfei An ◽

Hui Gong ◽

Tiandou Hu ◽

...

Keyword(s):

Signal To Noise Ratio ◽

High Energy ◽

High Energy Resolution ◽

Double Crystal ◽

Time Resolved ◽

Edge Structure ◽

X Ray ◽

Double Crystal Monochromator ◽

Good Signal ◽

X Ray Absorption

A new quick-scanning X-ray absorption fine-structure (QXAFS) system has been established on beamline 1W1B at the Beijing Synchrotron Radiation Facility. As an independent device, the QXAFS system can be employed by other beamlines equipped with a double-crystal monochromator to carry out quick energy scans and data acquisition. Both continuous-scan and trapezoidal-scan modes are available in this system to satisfy the time scale from subsecond (in the X-ray absorption near-edge structure region) to 1 min. Here, the trapezoidal-scan method is presented as being complementary to the continuous-scan method, in order to maintain high energy resolution and good signal-to-noise ratio. The system is demonstrated to be very reliable and has been combined with in situ cells to carry out time-resolved XAFS studies.

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Soft X-ray excited colour-centre luminescence and XANES studies of calcium oxide

Canadian Journal of Chemistry ◽

10.1139/v07-109 ◽

2007 ◽

Vol 85 (10) ◽

pp. 853-858 ◽

Cited By ~ 4

Author(s):

JY Peter Ko ◽

Franziskus Heigl ◽

Yun Mui Yiu ◽

Xing-Tai Zhou ◽

Tom Regier ◽

...

Keyword(s):

Calcium Oxide ◽

Density Functional ◽

X Rays ◽

Colour Centre ◽

Time Resolved ◽

Edge Structure ◽

Colour Centres ◽

X Ray ◽

Optical Luminescence ◽

X Ray Absorption

In this study, we show that colour centres can be produced by irradiating calcium oxide with soft X-rays from a synchrotron radiation source. Using the X-ray excited optical luminescence (XEOL) technique, two colour centres, F-centre, and F+-centre can be identified. These colour centres emit photons at characteristic wavelengths. In addition, by performing time-resolved XEOL (TRXEOL), we are able to reveal timing and decay characteristics of the colour centres. We also present X-ray absorption near-edge structure (XANES) spectra collected across oxygen K-edge, calcium L3,2-edge, and calcium K-edge. Experimental results are compared with density functional theory (DFT) calculations.Key words: calcium oxide, colour centre, synchrotron, X-ray excited optical luminescence, X-ray absorption near-edge structure.

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Picosecond and femtosecond X-ray absorption spectroscopy of molecular systems

Acta Crystallographica Section A Foundations of Crystallography ◽

10.1107/s010876730904968x ◽

2010 ◽

Vol 66 (2) ◽

pp. 229-239 ◽

Cited By ~ 55

Author(s):

Majed Chergui

Keyword(s):

Absorption Spectroscopy ◽

Structural Dynamics ◽

Intramolecular Electron Transfer ◽

Time Resolved ◽

Edge Structure ◽

X Ray ◽

Molecular Systems ◽

Recent Developments ◽

Amorphous Media ◽

X Ray Absorption

The need to visualize molecular structure in the course of a chemical reaction, a phase transformation or a biological function has been a dream of scientists for decades. The development of time-resolved X-ray and electron-based methods is making this true. X-ray absorption spectroscopy is ideal for the study of structural dynamics in liquids, because it can be implemented in amorphous media. Furthermore, it is chemically selective. Using X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) in laser pump/X-ray probe experiments allows the retrieval of the local geometric structure of the system under study, but also the underlying photoinduced electronic structure changes that drive the structural dynamics. Recent developments in picosecond and femtosecond X-ray absorption spectroscopy applied to molecular systems in solution are reviewed: examples on ultrafast photoinduced processes such as intramolecular electron transfer, low-to-high spin change, and bond formation are presented.

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X-ray spectroscopic analysis of Liesegang patterns in Mn–Fe-based Prussian blue analogs

Journal of Analytical Atomic Spectrometry ◽

10.1039/c6ja00173d ◽

2016 ◽

Vol 31 (8) ◽

pp. 1658-1672 ◽

Cited By ~ 13

Author(s):

Hisashi Hayashi ◽

Hitoshi Abe

Keyword(s):

Prussian Blue ◽

Spectroscopic Analysis ◽

Time Resolved ◽

Edge Structure ◽

X Ray ◽

Prussian Blue Analogs ◽

X Ray Absorption

We performed time-resolved X-ray fluorescence (XRF) and position-dependent X-ray absorption near-edge structure (XANES) measurements on Liesegang patterns in Mn–Fe-based Prussian blue analogs.

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