The variation in ionization enthalpy for dⁿ configuration is influenced by the attraction of electrons towards the nucleus, repulsion between electrons, and exchange energy. Exchange energy, proportional to the number of possible pairs of parallel spins, increases stability by following ...

The breaks in the trend of increasing second and third ionization enthalpy occur for Mn²⁺ and Fe³⁺ in the 3d series, where these ions have d⁵ configuration. Similar breaks occur at corresponding elements in later transition series, and these anomalies ...

The addition of electrons to the 3d orbitals in the 3d series enhances the shielding effect of 3d electrons, effectively shielding 4s electrons from the increasing nuclear charge. As a result, the atomic radii decrease less rapidly, leading to only ...

The irregular trend in the first ionization enthalpy is attributed to the alteration of relative energies between 4s and 3d orbitals upon the removal of one electron, affecting the shielding of 4s electrons by the increasing nuclear charge along the ...

The variation in ionization enthalpy along a series of transition elements is less pronounced than in a period of non-transition elements. While the first ionization enthalpy generally increases, the increase in the second and third ionization enthalpies is significantly higher ...