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Updated: Sep 11, 2025

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
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Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid

Published on: January 25, 2020

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探索密度函数对多环芳的无声振动的精度函数的研究

Nivedhitha Palanisamy1, Subrata Banik1

  • 1Department of Chemistry, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur 613401 Tamil Nadu, India.

The journal of physical chemistry. A
|August 13, 2025
PubMed
概括

选择正确的密度功能理论 (DFT) 方法对于准确的多环芳 (PAH) 振动结构计算至关重要. 像B3LYP这样的混合GGA函数为这些复杂分子提供了比meta-GGA函数更好的性能.

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Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
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Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
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