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Updated: Jul 5, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Theoretical studies on the thermochemistry of stable closed-shell C1 and C2 brominated hydrocarbons
1College of Chemistry, South China University of Technology, Guangzhou 510640, China. wanglm@scut.edu.cn
Abstract:
The enthalpies of formation of stable closed shell C1 and C2 brominated hydrocarbons have been predicted using Gaussian-3X model chemistry. The entropy, heat capacity, and thermal corrections are calculated from B3LYP/6-31G(2df,p) geometries and vibrational frequencies using rigid-rotor-harmonic-oscillator approximation, except for the quantities of the internal rotations in ethanes, which are calculated using the quantum-mechanical energy levels. Enthalpies of formation have been obtained from G3X atomization and isodesmic reactions. Good agreement is observed on the well-established experimental enthalpies of formation of CH 3Br, CH 2Br 2, CH 2ClBr, and C 2H 3Br from the high-resolution threshold photoelectron photoionization coincidence study.
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