key term - Excited state

Definition

An excited state refers to a higher energy configuration of an atom or molecule compared to its ground state, where electrons occupy the lowest available energy levels. In this state, one or more electrons have absorbed energy, allowing them to move to higher energy orbitals. The excited state is crucial for understanding electronic transitions in coordination compounds and is represented in Tanabe-Sugano diagrams.

5 Must Know Facts For Your Next Test

1. In an excited state, electrons can occupy orbitals with higher principal quantum numbers, which increases the potential for chemical reactivity.
2. Excited states are often short-lived; they quickly return to the ground state, releasing energy in the form of light or heat.
3. The energies required to promote electrons to excited states can be determined using spectroscopic techniques, providing insight into molecular structure.
4. In Tanabe-Sugano diagrams, the positions of excited states are illustrated alongside their corresponding ground states, showing how ligand fields influence electronic configurations.
5. Different ligands cause different amounts of splitting in d-orbitals; understanding this splitting is essential for predicting colors and magnetic properties in transition metal complexes.

Review Questions

• How does the concept of excited states relate to electronic transitions in coordination complexes?
  • Excited states are directly linked to electronic transitions because when a coordination complex absorbs energy, its electrons can jump from lower energy orbitals to higher ones, creating an excited state. This process is essential for understanding how light interacts with these complexes. The transitions observed in spectroscopy reflect these jumps, which helps chemists identify specific properties of the coordination compounds based on their excited states.
• Discuss the significance of Tanabe-Sugano diagrams in representing the excited states of transition metal complexes.
  • Tanabe-Sugano diagrams provide a visual representation of the energy levels associated with both ground and excited states of transition metal complexes under various ligand fields. By plotting these energies, chemists can see how different ligands affect the splitting of d-orbitals and thus influence electronic transitions. This insight is vital for predicting the spectral properties and reactivity of coordination compounds.
• Evaluate how understanding excited states can impact our comprehension of light absorption and color in transition metal complexes.
  • Understanding excited states is critical for grasping how transition metal complexes absorb light and exhibit color. When light hits these complexes, specific wavelengths correspond to the energy required for electrons to jump to excited states. The color observed is due to the wavelengths that are not absorbed but instead transmitted or reflected. This relationship allows chemists to predict and manipulate color based on ligand choices and molecular structure, which is essential in applications like dyes and sensors.

Related terms

ground state:

The lowest energy state of an atom or molecule, where all electrons are in the most stable configuration.

electronic transitions:

The movement of an electron from one energy level to another, often accompanied by the absorption or emission of energy in the form of light.

Tanabe-Sugano diagram: A graphical representation used to describe the energy levels and transitions of d-electron systems in coordination complexes, illustrating how different ligand fields affect the splitting of d-orbitals.