Bonding In Coordination Compounds
Chapter Name : Coordination Compounds |
Sub Topic Code : 102_12_09_05_05 |
Topic Name : Bonding In Coordination Compounds |
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Sub Topic Name : Color In Coordination Compounds |
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Introduction
Coordination complex or metal complex, consists of an atom or ion (usually metallic), and a surrounding array of bound molecules or anions, that are in turn known as ligands or complexing agents.
Pre-Requisites:
Coordination Compounds
Activity:
Nickel tetracarbonyl.
Real Life Question:
What are Coordination Compounds?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Crystal field theory | Crystal field theory (CFT) is a model that describes the breaking of degeneracies of electronic orbital states, usually d or f orbitals, due to a static electric field produced by a surrounding charge distribution (anion neighbors). |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Ethylenediaminetetraacetic acid | Ethylenediaminetetraacetic acid (EDTA) is used for estimation of Ca2+ and Mg2+ in hard water. |
Real life uses :
Study of organometals.
Places to visit :
Pharmacy.
Practical examples around us
| Examples | Explainations |
|---|---|
| Nickel tetracarbonyl | It is an intermediate in the Mond process for the purification of nickel and a reagent in organometallic chemistry. |
What you learn in Theory:
When ligands attach to a transition metal to form a coordination complex, electrons in the d orbital split into high energy and low energy orbitals. The difference in energy of the two levels is referred to as ?, which is a property both of the metal and the ligands. If ? is large, and a lot of energy is required to get electrons into the high energy orbitals, the electrons will instead pair up in the lower energy orbitals, resulting in a complex that is called “low spin”.
What you learn in Practice:
Different ligands are associated with either high or low spin--a ligand that is “strong field” will result in a large ? and a low spin configuration, while a ligand that is “weak field” will result in a small ? and a high spin configuration.