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Updated: May 24, 2025

Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids

Published on: May 27, 2020

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基于 ΔSCF 和 ROKS DFT 的方法可以预测有机分子中单元三元差的反转吗?

Danillo Valverde1,2, Gaetano Ricci1, Juan Carlos Sancho-García3

  • 1Laboratory for Computational Modeling of Functional Materials, Namur Institute of Structured Matter, University of Namur, Rue de Bruxelles, 61, Namur B-5000, Belgium.

Journal of chemical theory and computation
|March 1, 2025
PubMed
概括

反向单点三点间隙 (INVEST) 材料对OLED显示出有前途的可能性. 德尔塔自相一致场 (ΔSCF) 计算,特别是PBE0,可以准确地预测它们的反转能量差距,与ROKS方法不同.

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Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
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Infrared spectroscopy, also known as vibrational spectroscopy, is mainly used to determine the types of bonds and functional groups in molecules. In aldehydes and ketones, the carbonyl (C=O) bond shows an absorption around 1710 cm-1. The C=O bond vibration of an aldehyde occurs at lower frequencies than that of a ketone. In addition to the C=O absorption in an aldehyde, the aldehydic C–H bond also gives two peaks in the 2700–2800 cm-1 range. This absorption, coupled with the...
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In an NMR sample, precise measurement of the absolute absorption frequencies of nuclei is difficult. A standard internal reference compound is added, and the frequency difference between the reference signal and sample signals is measured.
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