The reason for the stability of ${\mathrm{Gd}}^{3+}$ ion is :

The reason for the stability of Gd³⁺ ion lies in its unique electronic configuration. Gadolinium (Gd) has an atomic number of 64, and its electronic configuration in the neutral state is:

Gd = [Xe] 4f⁷ 5d¹ 6s²

When Gadolinium loses three electrons to form the Gd³⁺ ion, the resulting configuration becomes:

Gd³⁺ = [Xe] 4f⁷

The reason for the stability of Gd³⁺ ion is the presence of a half-filled 4f subshell. A half-filled subshell is considered particularly stable because it has a symmetrical distribution of electrons and a higher exchange energy. This stability is a result of quantum mechanical effects, where half-filled orbitals have lower energy and greater exchange interactions, making them energetically favorable.

In summary, the reason for the stability of Gd³⁺ ion is its half-filled 4f⁷ electronic configuration. This configuration contributes to its overall stability due to increased symmetry and exchange energy. The removal of the 5d¹ and 6s² electrons leads to a state where the remaining 4f electrons create a stable, half-filled structure.

Key Takeaways

• The reason for the stability of Gd³⁺ ion is its half-filled 4f⁷ subshell.
• Half-filled configurations are stable due to symmetrical electron distribution and exchange energy.
• Neutral Gadolinium has the configuration [Xe] 4f⁷ 5d¹ 6s², and Gd³⁺ ion has [Xe] 4f⁷.