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Updated: Jun 4, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
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在Au102(p-MBA) 44集群的电子和振动签名

Eero Hulkko1, Olga Lopez-Acevedo, Jaakko Koivisto

  • 1Nanoscience Center, Department of Chemistry, P.O. Box 35, FI-40014 University of Jyväskylä, Finland.

Journal of the American Chemical Society
|February 26, 2011
PubMed
概括

测量和计算金纳米集群的光学吸收,揭示了关键的电子过渡. 合物交换没有影响核心电子属性,为未来的纳米集群应用提供了基准.

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¹H NMR: Complex Splitting01:13

¹H NMR: Complex Splitting

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UV–Vis Spectroscopy: Molecular Electronic Transitions

In Ultraviolet–Visible (UV–Vis) spectroscopy, the absorption of electromagnetic radiation is used to probe the electronic structure of molecules. This technique provides insights into molecular electronic transitions, particularly the movement of electrons between different molecular orbitals. Radiation is absorbed if the energy of the electromagnetic radiation passing through the molecule is precisely equal to the energy difference between the excited and ground states. During this process,...
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Electronic Structure of Atoms


An atom comprises protons and neutrons, which are contained inside the dense, central core called the nucleus, with electrons present around the nucleus. Taking into account the wave–particle duality of electrons and the uncertainty in position around the nucleus, quantum mechanics provides a more accurate model for the atomic structure. It describes atomic orbitals as the regions around the nucleus where electrons of discrete energy exist, characterized by four quantum numbers:  n, l, ml, and...
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π Electron Effects on Chemical Shift: Overview

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When protons A and X are coupled, their nuclear spin energy levels are slightly modified. This is because the energy required to excite proton A to a spin state parallel to proton X is slightly different from the energy required for it to become anti-parallel to spin X. Consequently, there are two possible excitation frequencies for A (A1 and A2), depending on the spin state of X, and vice versa. The mutual nature of coupling implies that the difference between frequencies A1 and A2, indicated...