相关实验视频

Updated: Sep 20, 2025

Low-energy Cathodoluminescence for OxyNitride Phosphors
07:03

Low-energy Cathodoluminescence for OxyNitride Phosphors

Published on: November 15, 2016

10.8K

构建和描述稀土复合物,以使用四乙烯乙烯二酸和三酸化配体进行有效的排放调节

Chuan-Bing Hou1,2, Gui-Xiong Guo1, Li-Xiong Dai3

  • 1Department of Chemistry, Capital Normal University, Beijing 100048, China. E-mail: jinqh@cnu.edu.cn, jinqh204@163.com.

Dalton transactions (Cambridge, England : 2003)
|May 28, 2025
PubMed
概括

合成了使用四乙烯乙烯双酸盐和联体 2,2′:6′,2′′-特皮里丁 (TPY) 或 2,4,6-tri(2-pyridyl) -s-triazine (TPTZ) 的新型兰化物复合物. 基于TPY的复合物显示了增强的发光,这表明了高效发光装置的潜力.

更多相关视频

Luminescence Resonance Energy Transfer to Study Conformational Changes in Membrane Proteins Expressed in Mammalian Cells08:31

Luminescence Resonance Energy Transfer to Study Conformational Changes in Membrane Proteins Expressed in Mammalian Cells

Published on: September 16, 2014

12.2K
Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging13:21

Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging

Published on: July 21, 2011

15.1K

相关概念视频

EDTA: Chemistry and Properties01:22

EDTA: Chemistry and Properties

Polydentate ligands are most widely used in complexometric titrations because they form more stable complexes with the metal ions than mono- or bidentate ligands due to the chelate effect. Examples of polydentate ligands are ethylenediaminetetraacetic acid (EDTA), crown ethers, and cryptands. The most important feature of optimal polydentate ligands is the ability to form 1:1 complexes in a single-step process. Amino carboxylic acid derivatives are frequently used as complexing agents. EDTA is...
2.2K
Complexation Equilibria: The Chelate Effect01:19

Complexation Equilibria: The Chelate Effect

In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
685
Crystal Field Theory - Tetrahedral and Square Planar Complexes02:46

Crystal Field Theory - Tetrahedral and Square Planar Complexes

Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
44.8K
Valence Bond Theory02:42

Valence Bond Theory

Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
9.7K
Complexometric Titration: Ligands00:43

Complexometric Titration: Ligands

Different monodentate and polydentate ligands are used as complexing agents in complexometric titration reactions. The formation of complexes by mono- and bidentate ligands involves two or more intermediate steps, limiting their use as complexing agents. In comparison, polydentate ligands can form complexes with metal ions in a single-step process, facilitating sharper end points. This means polydentate ligands, such as amino carboxylic acid derivatives, are most commonly employed in...
1.1K
Crystal Field Theory - Octahedral Complexes02:58

Crystal Field Theory - Octahedral Complexes

Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
28.0K