相关实验视频

Updated: Jun 13, 2025

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals

Published on: April 19, 2019

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有效的随机相近似对二极值

Reza G Shirazi1, Vladimir V Rybkin1, Michael Marthaler1

  • 1HQS Quantum Simulations GmbH, Rintheimer Str. 23, 76131 Karlsruhe, Germany.

The Journal of chemical physics
|September 16, 2024
PubMed
概括

我们开发了一种具有两个不配对电子的二基分子模型. 我们的方法,使用随机相近似 (RPA),准确地预测单元-三元分裂,与先进的计算化学结果保持一致.

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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization08:22

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Radical Reactivity: Overview01:11

Radical Reactivity: Overview

Radicals, the highly reactive species, gain stability by undergoing three different reactions. The first reaction involves a radical-radical coupling, in which a radical combines with another radical, forming a spin‐paired molecule. The second reaction is between a radical and a spin‐paired molecule, generating a new radical and a new spin‐paired molecule. The third reaction is radical decomposition in a unimolecular reaction, forming a new radical and a spin‐paired...
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Radical Formation: Overview01:03

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A bond can be broken either by heterolytic bond cleavage to form ions or homolytic bond cleavage to yield radicals. A fishhook arrow is used to represent the motion of a single electron in homolytic bond cleavage. There are two main sources from which radicals can be formed:
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the...
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Radical Formation: Addition00:47

Radical Formation: Addition

Radicals can be formed by adding a radical to a spin-paired molecule. This is typically observed with unsaturated species, where the addition of a radical across the π bond leads to the production of a new radical by dissolving the π bond. For example, the addition of a Br radical to an alkene yields a carbon-centered radical.
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Ideally, an unpaired electron shows a single peak in the EPR spectrum due to the transition between the two spin energy states. However, coupling interactions can occur between the spins of the unpaired electron and any neighboring spin-active nuclei. This hyperfine coupling results in hyperfine splitting, where the EPR signal is split into multiplets. The signals split into 2nI + 1 peaks, where n is the number of equivalent nuclei and I is the nuclear spin. These splitting patterns provide...
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This lesson delves into the geometry of a radical, which is influenced by the electronic structure of the molecule. The principle is similar to that of a lone pair, where the unpaired electron influences the geometry at the radical center.
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