X-ray spectroscopy on the active ion in laser crystals

X-ray absorption and (resonant) emission spectroscopies combined measure the differences in crystal field parameters for the ground and core-excited states.

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CTM4DOC: electronic structure analysis from X-ray spectroscopy

Journal of Synchrotron Radiation ◽

10.1107/s1600577516012443 ◽

2016 ◽

Vol 23 (5) ◽

pp. 1264-1271 ◽

Cited By ~ 12

Author(s):

Mario Ulises Delgado-Jaime ◽

Kaili Zhang ◽

Josh Vura-Weis ◽

Frank M. F. de Groot

Keyword(s):

Electronic Structure ◽

Transition Metal ◽

Crystal Field ◽

Excited States ◽

Spin Systems ◽

Core Hole ◽

X Ray ◽

Mixed Spin ◽

Crystal Field Parameters ◽

Electron Crystal

Two electronic structure descriptions, one based on orbitals and the other based on term symbols, have been implemented in a new Matlab-based program,CTM4DOC. The program includes a graphical user interface that allows the user to explore the dependence of details of electronic structure in transition metal systems, both in the ground and core-hole excited states, on intra-atomic electron–electron, crystal-field and charge-transfer interactions. The program can also track the evolution of electronic structure features as the crystal-field parameters are systematically varied, generating Tanabe–Sugano-type diagrams. Examples on first-row transition metal systems are presented and the implications on the interpretation of X-ray spectra and on the understanding of low-spin, high-spin and mixed-spin systems are discussed.

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An Intuitive Method for the Determination of Crystal-Field Parameters in Laser Crystals

MRS Proceedings ◽

10.1557/proc-329-203 ◽

1993 ◽

Vol 329 ◽

Author(s):

Frederick G. Anderson ◽

H. Weidner ◽

P. L. Summers ◽

R. E. Peale ◽

B. H. T. Chai

Keyword(s):

Crystal Field ◽

Irreducible Representations ◽

Laser Crystals ◽

Intuitive Method ◽

Crystal Field Parameters ◽

Intuitive Interpretation

AbstractExpanding the crystal field in terms of operators that transform as the irreducible representations of the Td group leads to an intuitive interpretation of the crystal-field parameters. We apply this method to the crystal field experienced by Nd3+ dopants in the laser crystals YLiF4, YVO4, and KLiYF5.

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Crystal-Field Mediated Electronic Transitions of EuS up to 35 GPa

10.21203/rs.3.rs-1027058/v1 ◽

2021 ◽

Author(s):

Virginia Monteseguro ◽

Jose Antonio Barreda-Argüeso ◽

Javier Ruiz-Fuertes ◽

Angelika Rosa ◽

Holger L. Meyerheim ◽

...

Keyword(s):

Electronic Structure ◽

Crystal Field ◽

Local Structure ◽

Electronic Transitions ◽

Metallic State ◽

X Ray ◽

Half Metal ◽

Consistent Model ◽

X Ray Absorption ◽

Pressure Evolution

Abstract An advanced experimental and theoretical model to explain the correlation between the electronic and local structure of Eu2+ in two different environments within a same compound, EuS, is presented. EuX monochalcogenides (X: O, S, Se, Te) exhibit anomalies in all their properties around 14 GPa with a semiconductor to metal transition. Although it is known that these changes are related to the 4f75d0 → 4f65d1 electronic transition, no consistent model of the pressure-induced modifications of the electronic structure currently exists. We show, by optical and x-ray absorption spectroscopy, and by ab initio calculations up to 35 GPa, that the pressure evolution of the crystal field plays a major role in triggering the observed electronic transitions from semiconductor to the half-metal and finally to the metallic state.

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