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Updated: Jul 13, 2026

Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
08:51

Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers

Published on: August 18, 2017

四极色谱体中的电荷不稳定性:对称性破坏和solvatochromism

Francesca Terenziani1, Anna Painelli, Claudine Katan

  • 1Dipartimento di Chimica GIAF, Università di Parma and INSTM-UdR Parma, Parco Area delle Scienze 17/a, 43100 Parma, Italy. francesca.terenziani@unipr.it

Journal of the American Chemical Society
|December 7, 2006
PubMed
概括

我们在四极色素中探索了非线性光学 (NLO) 的对称性破坏. 我们的模型预测了不同的光谱行为,并指导了用于二光子吸收 (TPA) 应用的高效染料的设计.

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Properties of Transition Metals02:58

Properties of Transition Metals

Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3–12 are transition elements. The f-block elements, also called inner transition metals (the lanthanides and actinides), also meet this criterion because the d orbital is partially occupied before the f orbitals.
Stereoisomerism02:52

Stereoisomerism

Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
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Colors and Magnetism

Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
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Photochemical Electrocyclic Reactions: Stereochemistry

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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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Imperfections in Crystal Structure: Non-Stoichiometric Defects

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