Natural values of coupling constants and cosmological inflation in a supersymmetric model

This work evaluates the quality of exchange coupling constant and spin crossover gap calculations using density functional theory corrected by the Approximate Projection model. Results show that improvements using the Approximate Projection model range from modest to significant. This study demonstrates that, at least for the class of systems examined here, spin-projection generally improves the quality of density functional theory calculations of J-coupling constants and spin crossover gaps. Furthermore, it is shown that spin-projection can be important for both geometry optimization and energy evaluations. The Approximate Project model provides an affordable and practical approach for effectively correcting spin-contamination errors in molecular exchange coupling constant and spin crossover gap calculations.

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Q & A. Lisa Randall. [interview]

10.31219/osf.io/sjfxn ◽

2019 ◽

Author(s):

Adib Rifqi Setiawan

Keyword(s):

New York ◽

New York City ◽

Particle Physics ◽

Harvard University ◽

The Past ◽

Talent Search ◽

Cosmological Inflation ◽

On Line ◽

Theoretical Physicist ◽

Fundamental Forces

Lisa Randall is a theoretical physicist working in particle physics and cosmology. She was born in Queens, New York City, on June 18, 1962. Lisa Randall is an alumna of Hampshire College Summer Studies in Mathematics; and she graduated from Stuyvesant High School in 1980. She won first place in the 1980 Westinghouse Science Talent Search at the age of 18; and at Harvard University, Lisa Randall earned both a BA in physics (1983) and a PhD in theoretical particle physics (1987) under advisor Howard Mason Georgi III, a theoretical physicist. She is currently Frank B. Baird, Jr. Professor of Science on the physics faculty of Harvard University, where he has been for the past a decade. Her works concerns elementary particles and fundamental forces, and has involved the study of a wide variety of models, the most recent involving dimensions. She has also worked on supersymmetry, Standard Model observables, cosmological inflation, baryogenesis, grand unified theories, and general relativity. Consequently, her studies have made her among the most cited and influential theoretical physicists and she has received numerous awards and honors for her scientific endeavors. Since December 27, 2010 at 00:42 (GMT+7), Lisa Randall is Twitter’s user with account @lirarandall. “Thanks to new followers. Interesting how different it feels broadcasting on line vs.via book or article. Explanations? Pithiness? Rapidity?” is her first tweet.

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The Electron Effect of Aromatic Group: Control Conformation of 2-Aromatic Cyclododecanone Derivatives

Current Organic Chemistry ◽

10.2174/1385272824999200607175514 ◽

2020 ◽

Vol 24 (10) ◽

pp. 1139-1147

Author(s):

Yang Mingyan ◽

Wang Daoquan ◽

Wang Mingan

Keyword(s):

1H Nmr ◽

13C Nmr ◽

Nmr Spectra ◽

Coupling Constants ◽

The Other ◽

Repulsive Interaction ◽

X Ray Diffraction ◽

X Ray ◽

Electron Effect ◽

Group Control

2-Phenylcyclododecanone and 2-cyclohexylcyclododecanone derivatives were synthesized and characterized by 1H NMR, 13C NMR, HR-ESI-MS and X-ray diffraction. Their preferred conformations were analyzed by the coupling constants in the 1H NMR spectra and X-ray diffraction, which showed the skeleton ring of these derivatives containing [3333]-2-one conformation, and the phenyl groups were located at the side-exo position of [3333]-2-one conformation due to the strong π-π repulsive interaction between the π- electron of benzene ring and π-electron of carbonyl group. The cyclohexyl groups were located at the corner-syn or the side-exo position of [3333]-2-one conformation depending on the hindrance of the other substituted groups. The π-π electron effect played a crucial role in efficiently controlling the preferred conformation of 2-aromatic cyclododecanone and the other 2-aromatic macrocyclic derivatives with the similar preferred square and rectangular conformations.

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