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Updated: Feb 18, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
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循环丁的自动化:多配置对密度函数理论在不受限制的Kohn-Sham密度函数理论没有高精度的情况下,可以获得高精度

Aiswarya M Parameswaran1, Donald G Truhlar1

  • 1Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States.

Journal of the American Chemical Society
|February 16, 2026
PubMed
概括

对密度函数方法进行了比较,以计算环丁的自动化障碍. 多配置对密度函数理论 (MC-PDFT) 对于这种多配置反应,比不受限制的Kohn-Sham (UKS) 计算显示出更高的精度.

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This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
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Conjugated dienes have lower heats of hydrogenation than cumulated and isolated dienes, making them more stable. The enhanced stabilization of conjugated systems can be understood from their π molecular orbitals.
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