光谱化学系列和肾上腺素系列之间的差异|比较类似术语之间的差异

Thekey differencebetween spectrochemical series and nephelauxetic series is thatspectrochemical series of ligands have配体弱in the left side and强壮的配体在右侧能力较低来形成covalent bondswith metal ions and ligands in the right side have a更大的能力来形成the covalent bonds.

光谱系列和肾上腺素系列的配体和金属离子按顺序排列。基于配体和金属离子的顺序从一个系列到另一个的参数不同。

内容

1.Overview and Key Difference
2.What is a Spectrochemical Series
3.What is a Nephelauxetic Series
4.Side by Side Comparison – Spectrochemical Series vs Nephelauxetic Series in Tabular Form
5.概括

What is a Spectrochemical Series?

Spectrochemical series is a list of ligands and metal ions arranged according to the ligand strength and the oxidation state of metal ions. This series is very useful in identifying whether acoordination complexis a high spin or low spin. The concept about spectrochemical series first evolved in 1938. This series was suggested based on the data obtained from absorption spectra of cobalt complexes.

Figure 01: A Part of the Spectrochemical Series

Ligands in this series are arranged according to the ligand strength. Here, ligands with a weak strength are placed in the left side of the spectrochemical series while strong ligands are placed in the right side of the series. The weak ligands are referred to as ligands that cannot cause forcible pairing of electrons in the 3d energy level, thus forming high spin complexes. Stronger ligands can cause forcible pairing of electrons in the 3d energy level and form low spin coordination complexes. The order of this series is arranged according to the donor or acceptor ability of the ligands.

除配体外，金属离子还可以在光谱级数中排列。配体场的序列分裂用于排列金属离子。但是，该顺序与配体的身份无关。此外，关于金属离子的光谱化学系列有两种观察。配体场的值随着金属离子的氧化态增加而增加。同样，配体场拆分值还增加了一组元素周期表。

What is Nephelauxetic Series?

肾上腺素系列是根据其肾上腺素效应排列的配体或金属离子的列表。该术语主要用于过渡金属离子。nephelauxetic一词是指RACAH相互作用排斥参数的减少。该参数的符号为“ b”，当过渡金属无离子形成配体配体的复合物时，可以测量它。

RACAH参数的减少表明金属D轨道中两个电子之间的排斥力较小，并且轨道在复合物中较大。这称为复合物的电子云膨胀，这对于确定肾上腺素效应很重要。

When ligands are arranged in a list according to the measured nephelauxetic effect, it is closely similar to the spectrochemical series. However, this arrangement generally reflects the ability of the ligands to form covalent bonds with metal ions. The ligands in the left side have a lesser effect of forming a covalent bond with a metal ion while the ligands in the right side have a greater effect.

What is the Difference Between Spectrochemical Series and Nephelauxetic Series?

The key difference between spectrochemical series and nephelauxetic series is that spectrochemical series of ligands have weak ligands in the left side and strong ligands in the right side whereas nephelauxetic series contains ligands with small ability to form covalent bonds with metal ions and ligands in the right side have a large ability to form the covalent bonds.

Moreover, metal ions in a spectrochemical series are arranged in the order of ligand field split value (or the oxidation state) while the metal ions in a nephelauxetic series are arranged in the increasing order of nephelauxetic effect.

Below is a summary of the difference between spectrochemical series and nephelauxetic series in tabular form.

摘要 - 光谱化学系列与Nephelauxetic系列

光谱系列和肾上腺素系列的配体和金属离子按顺序排列。The key difference between spectrochemical series and nephelauxetic series is that spectrochemical series of ligands have weak ligands on the left side and strong ligands on the right side whereas nephelauxetic series contains ligands with weaker ability to form covalent bonds with metal ions and ligands in the right side have a greater ability to form the covalent bonds.

Reference:

1.“ B.2。光谱化学系列。”化学库，库，2019年6月5日，Available here.
2. “Spectrochemical Series.” Wikipedia, Wikimedia Foundation, 16 Apr. 2020,Available here.
3. “20.9A: The Nephelauxetic Effect.” Chemistry LibreTexts, Libretexts, 5 June 2019,Available here.