Explaining the Anomaly in Atomic Radii of Transition Metals

[sciencenerd]

Could anybody help me with this?

The atomic radii of the transition metals show some anomaly in their atomic radii as
compared to those elements in Group 1A-7A, which generally shows a decrease as one
goes from left to right in a period. The atomic radii of the transition metals decrease as
do those in Groups 1A-7A, but then they increase. For example, Sc has an atomic radius
of 162 pm and the atomic radii decrease until Ni to 124 pm, but Cu an Zn have larger
atomic radii than Ni and Zn is even larger than Cu. How do you explain this?

 

[Drik Paul]

Sciencenerd,
It is due to the repulsion between the electrons of the shells which increases the atomic radius due to the increase in the charge

 

[Blueshift5]

The anomaly in atomic radii of transition metals can be explained by their electronic configurations and the concept of effective nuclear charge. In transition metals, electrons are added to the d orbitals, which are more diffuse and have less shielding from the inner electron shells. This results in a larger effective nuclear charge, pulling the outer electrons closer to the nucleus and decreasing the atomic radius. However, as we move across the period, the d orbitals become more filled and the electrons experience more repulsion from each other, resulting in a slight increase in atomic radius. This effect is further amplified in the case of copper and zinc, where the completely filled d orbitals result in a larger atomic radius compared to the preceding elements. Overall, the anomaly in atomic radii of transition metals is a result of the complex interplay between electronic configurations, effective nuclear charge, and electron repulsion.