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All You Need to Know About F Orbitals

F orbitals are one of the four orbitals that are found around the nucleus. This article is an in-detail explanation of f-orbitals and their significance.

F orbitals are the orbitals that, in total, have the affinity to accommodate 14 electrons in them. The shape of the f orbital is tetrahedral. Though the shape of the f orbital is more complex than the other orbitals, the rule of filling the orbital remains the same as that of p and the d orbitals. 

The alignment of the electrons is also found to be the same as that of the other two orbitals. F orbital resembles the d orbitals when it is completely filled. But when f orbitals are cut into half, eight lobes are found instead of the four lobes like d orbitals. 

What are atomic orbitals, and what is meant by f orbital? 

Atomic orbitals are the quantum refinement of Bohr’s orbit. As the circular orbit has a fixed radius, the orbitals are the space that is mathematically derived and have probabilities of different types of containing an electron. 

An orbital is formed when the bonds present between the atoms combine with each other in the given molecule.

There are many types of articles present, namely s, p, d and f. These four types of orbitals are generally studied in chemistry in detail. 

S orbital

S orbital is the name given to the first orbital. It is spherical and symmetric around the nucleus. It looks like balls that are hollow inside and are made up of a chunky material, and the nucleus is found to be at its centre. There are many subshells found in an s orbital, for example, 2s, 3s, 4s etc. In the case of a hydrogen atom, the electron is first filled in the 1s subshell. As s orbital is close to the nucleus, the pull experienced on the electrons is quite high. The subshells like 1 s subshell and 2s are found to be nearer to the nucleus than any other subshell.

P orbital

As s orbital has the affinity to fill only 2 electrons, so not many electrons can fit into that orbital. That’s why the next successive orbital afters orbital is p orbital. After the 1s and 2s subshells have been completely filled, the electrons start to fill in the p orbital. After2s is filled, the electrons move to the 2p electrons. 

The shape of a p orbital looks like that of two similar balloons that have been tied around the nucleus. 

There are three subshells that are present in the p orbital. Mainly they are represented by the symbols like px, py, and Pz. The symbols x, y and z mainly represent the directions of the subshells in which they are arranged around the nucleus, and these directions constantly change as the atom moves in space. 

D orbital

Apart from these two orbitals, d and f orbitals are the other two types of orbitals present. There are 5 d orbitals, but their shapes are really complicated, and so are their names. These orbitals are found to be present at the third level. 

F orbital

F orbital is present at the fourth level. F orbital is found to be tetrahedral in shape. In total, 17 electrons can be accommodated in an f orbital. 

The F orbital has a very complex shape. 

The shape of the F orbital

The shape of the orbital is very complex. Though the shape is complex, the rule of filling of the electrons remains the same. The rule of alignment of the proton is the same as that of any p and d orbitals. 

When the f orbital gets completely filled, it just resembles the shape of the d orbital. But when it is cut into half, the f orbital divides into 8   lobes instead of the expected 4 lobes. This breaking of the lobes is based on the nucleus rotation, where the protons of opposite spin align on the points of the nucleus rotation. 

Types of f orbitals

The f orbitals can be divided into three types based on how they are aligned on the axes. 

  • Two lobes – The two lobes type of f orbitals have sigma bonding only. 

As only sigma bonding is present, it can help bond head to head along the z-axis present on it. 

  • Six lobes- The six lobes type of f orbitals have sigma as well as pie bonding present in it, or only fi bonding is present. 

The pi bond can form a bond along z axes, y axes and XY planes. 

  • Eight lobes – Eight lobes type of f orbitals can form pi bond or delta bond. The pie bond can be formed along any of the axes and alternatively form a delta bond with another f orbital and form a bimetallic complex.

Conclusion

All the atomic orbitals are distinct in their shape and size. The electron affinity differs for each type of atomic orbital. The shape, name as well as the size of the orbital is different, and so is their electron affinity. 

The electrons get filled according to the energies of each of the atomic orbitals.

faq

Frequently asked questions

Get answers to the most common queries related to the UPSC Examination Preparation.

How many types of f orbitals are present?

Ans. There are three types of orbitals present.

What is the shape of the orbital?

Ans.Tetrahedral is the shape of the f orbital generally.

What is the level of the f orbital?

Ans. The fourth level of the atomic orbit is the f orbital.