Analytical nuclear excited-state gradients for the Tamm-Dancoff approximation using uncoupled frozen-density embedding

Nuclear excited state lifetimes have been determined by direct timing, using a pulsed beam and a Ge(Li) detector in singles. Results are 35Cl (3163 keV), 46 ± 6 ps; 37Cl (3103 keV), 16 ± 9 ps; 39K (2813 keV), 71 ± 5 ps; 39K (3598 keV), 91 ± 27 ps. M2 and E3 transition strengths of the transitions in 35Cl and 37Cl are compared with previous theoretical calculations.

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Influence of Giant Nuclear-spin Polarisation on Resonant Gamma-ray Absorption and Emission

Australian Journal of Physics ◽

10.1071/p97057 ◽

1998 ◽

Vol 51 (2) ◽

pp. 339

Author(s):

R. N. Shakhmuratov

Keyword(s):

Excited State ◽

Nuclear Spin ◽

Ground State ◽

Gamma Ray ◽

Stimulated Emission ◽

Laser Pumping ◽

Nuclear Excited State ◽

Spin Polarisation ◽

Subsequent Quenching ◽

Amplification Without Inversion

We propose a new scheme of gamma-quanta amplification without inversion. Laser pumping of electron states creates giant nuclear-spin polarisation via the hyperfine interaction. This results in extreme cooling of the ground-state nuclear spin in a projection which does not absorb both laser pump and gamma-quanta according to selection rules for these transitions. Induced emission from the nuclear excited state is not influenced by the pump. Therefore gamma-quanta travelling inside the pump beam have an opportunity to induce stimulated emission without subsequent quenching by ground state nuclei.

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Renilla Bioluminescence: A Morphologic Approach to the Location of Photocytes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051050 ◽

1974 ◽

Vol 32 ◽

pp. 208-209

Author(s):

Ben O. Spurlock ◽

Milton J. Cormier

Keyword(s):

Excited State ◽

Ground State ◽

Molecular Basis ◽

Light Emission ◽

Chemical Basis ◽

Electronic Excited State ◽

Colonial Form ◽

The Common ◽

Eighteenth And Nineteenth Centuries ◽

Catalyzed Oxidation

The phenomenon of bioluminescence has fascinated layman and scientist alike for many centuries. During the eighteenth and nineteenth centuries a number of observations were reported on the physiology of bioluminescence in Renilla, the common sea pansy. More recently biochemists have directed their attention to the molecular basis of luminosity in this colonial form. These studies have centered primarily on defining the chemical basis for bioluminescence and its control. It is now established that bioluminescence in Renilla arises due to the luciferase-catalyzed oxidation of luciferin. This results in the creation of a product (oxyluciferin) in an electronic excited state. The transition of oxyluciferin from its excited state to the ground state leads to light emission.

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Integration of Core-Edge Spectroscopy Methods for the Study of Polymers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016323x ◽

1996 ◽

Vol 54 ◽

pp. 154-155

Author(s):

E. G. Rightor

Keyword(s):

Excited State ◽

Polymer Blends ◽

Gas Phase ◽

Spatial Resolution ◽

High Spatial Resolution ◽

Electronic States ◽

Core Electron ◽

Bulk Solids ◽

Development Application

Core edge spectroscopy methods are versatile tools for investigating a wide variety of materials. They can be used to probe the electronic states of materials in bulk solids, on surfaces, or in the gas phase. This family of methods involves promoting an inner shell (core) electron to an excited state and recording either the primary excitation or secondary decay of the excited state. The techniques are complimentary and have different strengths and limitations for studying challenging aspects of materials. The need to identify components in polymers or polymer blends at high spatial resolution has driven development, application, and integration of results from several of these methods.

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Examining the degradation of environmentally-daunting per- and poly-fluoroalkyl substances from a fundamental chemical perspective

Physical Chemistry Chemical Physics ◽

10.1039/d0cp02445g ◽

2020 ◽

Vol 22 (31) ◽

pp. 17659-17667 ◽

Cited By ~ 2

Author(s):

Antonio H. da S. Filho ◽

Gabriel L. C. de Souza

Keyword(s):

Excited State

In this work, ground and excited-state properties were used as descriptors for probing mechanisms as well as to assess potential alternatives for tackling the elimination of per- and poly-fluoroalkyl substances (PFAS).

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