Shielding

[Peter Nguyen 2I]

Can someone explain shielding and how it relates to multi electron atoms?

[Srikar_Ramshetty 1K]

Shielding within multi-electron atoms results from several factors. In hydrogen the presence of only one electron results in the electron feeling the full nuclear charge. However, in larger molecules electrons in orbitals further from the nucleus feel an effective nuclear charge. This is caused by repulsions between electrons. As electrons orbit the nucleus they are in proximity of feeling the negative charge of other electrons and therefore are not able to feel the full nuclear charge. This is also why the p and d orbitals have nodal planes where electron density is 0.

Hope this helps!

[Ibrahim Malik 1H]

Shielding works to reduce the pull outer electrons feel from the nucleus. In an element like Na, the one electron in the third outer shell is "shielded" from the effective nuclear charge. This outer electron does not have the same interactive forces and experiences weaker interactive forces than the two inner shells.

[Jonathan Cheng 3C]

Shielding is essentially when electrons in more outer shells experience less of an effective nuclear charge due to the electrons in the inner shells.

[KatrinaPho_2I]

An analogy that helps you better understand shielding was given by Dr. Lavelle during Friday's lecture. Imagine you're camping and standing next to the campfire. The heat that you feel from the fire can be compared to the force of attraction between an electron and the nucleus. If someone stands between you and the fire, you aren't going to feel as much heat from the fire anymore. This illustrates the fact that with multi electron atoms, the electrons on the outer shells are shielded from the electrons on the inner shells. These outer electrons experience a lesser force of attraction to the nucleus.

[ran2000]

Shielding is when electrons in lower energy levels "shielding" or preventing the nuclear charge from reaching electrons in outer shells. Thus, when there are more number of orbitals, there is more shielding on the outer electrons.