Δoct

Definition

Δoct, also known as crystal field splitting energy, represents the energy difference between the higher-energy and lower-energy sets of d-orbitals in an octahedral coordination complex. It plays a crucial role in determining the electronic structure and properties of transition metal complexes.

5 Must Know Facts For Your Next Test

1. Δoct is influenced by both the metal ion and the ligands surrounding it.
2. A large Δoct generally leads to low-spin configurations, while a small Δoct leads to high-spin configurations.
3. The magnitude of Δoct can be experimentally determined using spectroscopic methods such as UV-Vis spectroscopy.
4. Δoct is larger for complexes with strong-field ligands like CN⁻ and smaller for those with weak-field ligands like I⁻.
5. The value of Δoct affects not only electronic transitions but also magnetic properties of coordination compounds.

Review Questions

• What factors influence the magnitude of Δoct in an octahedral complex?
• How does Δoct affect the spin state (high-spin vs. low-spin) of a coordination compound?
• Which type of spectroscopic method can be used to determine the value of Δoct?

Related terms

High-Spin Complex:

A coordination complex where electrons occupy higher-energy orbitals, resulting from a small crystal field splitting energy (Δ).

Low-Spin Complex:

A coordination complex where electrons pair up in lower-energy orbitals, due to a large crystal field splitting energy (Δ).

Ligand Field Theory:

An extension of Crystal Field Theory that takes into account covalent as well as ionic aspects of metal-ligand interactions.