Question

"What is difference between shielding and electron electron repulsion. When I read this article , I came to know that both are different. First Read this paragraph and see the graph of ionization energy. Here we can see that author is writting that when we neglect electron electron repulsion we see that effective nuclear charge is increasing and ionization energy should increase but when we include this factor we find a drop in predicted ionization energy.

Now my questions is when we are talking about effective nuclear charge , haven't we already included the shielding factor which itself means repulsion that valence shell electron feels due to all other electrons in atom. So how author can say that he neglected the electron - electron repulsion while predicting ionization energy?

Answer 1

Shielding reduces the effective nuclear charge by accounting for the screening of inner electrons, while electron-electron repulsion focuses on the repulsive interactions among electrons.

Step-by-step explanation:

The difference between shielding and electron-electron repulsion lies in how these concepts affect atomic structure and ionization energies. Shielding involves the decrease of the effective nuclear charge experienced by an electron due to the presence of other electrons, especially core electrons, which are efficient at shielding valence electrons from the nucleus.

When discussing Zeff, it is indeed true that the shielding effect is taken into account, implying that electrons in inner shells partially cancel out the nuclear charge. However, while predicting ionization energy and factoring in Zeff, it's possible that the article simplifies the model by not considering the additional repulsion that valence electrons exert on each other.