In the subject of chemistry, one needs to study and have an inner for knowing how chemical bonds work. The literal definition of a bond is that it is the one that keeps the binding of the atoms with each other by interacting with them.
A chemical bond is further distinguished into many times, such as the covalent bond and the polar bond. Two main chemical bonds are the Sigma bond and the Pi bond.
Sigma Bond vs Pi Bond
The main difference between sigma bond and Pi bond is that a bond that is formed by a linear or a coaxial of two atoms overlapping each other is known as a sigma bond, and on the other hand, a bond which has its existence between two atoms having electrons from top to the bottom of an axis which later connects the nuclei is knowns as a Pi bond.
The formation of a sigma bond takes place in such a way when it overlaps two bonds in orbit. This happens when both the atoms appear to be face to face. This overlapping may appear between two s and p orbitals or even in-between ones and p orbitals in an axis. The sigma bonds can roam freely and independently rotate.
The formation of a pi bond takes place in a manner where it is formed by overlapping between two orbits in parallel or sideways. There is a high amount of energy emitted from this bond which makes it less stable. When it comes to participating in a Resonance without having to show its hyper- conjuration, that is when a pi bond comes into the picture.
Comparison Table Between Sigma Bond and Pi Bond
| Parameters of Comparison | Sigma Bond | Pi Bond |
| Strenghth | This is a strong bond. | This is a weak bond |
| Formation | Formed through the overlapping of atoms. | This formed between two sigma bonds. |
| Reaction | This bond is highly reactive. | This bond isn’t that reactive as a sigma bond. |
| Independence | These bonds are free and independent. | These bonds are not free and independent. |
| Overlapping | Overlapping of an atom in this bond can occur between one hybrid and one pure orbit or between both pure or both hybrid orbitals. | Overlapping of atoms in this bond takes place only between two non-hybrid orbitals. |
What is Sigma Bond?
The formation of a sigma bond takes place in such a way when it overlaps two bonds in orbit. This happens when both the atoms appear to be face to face. This overlapping may appear between two s and p orbitals or even in-between ones and p orbitals in an axis. The sigma bonds can roam freely and independently rotate.
A sigma bond is very less in emitting energy, which makes it more stable. A sigma Bond does not show any kind of Resonance or hyper-conjugation. There is an existence of a pair of electrons between every two atoms that can move to another atom. This helps them to be a Delocalized bond.
A compound that has a sigma that is localized can be fully elaborated by a single Lewis structure in compounding. The sigma bonds can roam freely and independently rotate. It is very easy to predict a bond’s length, a bond’s energy, and other factors when it comes to sigma bonds.
What is Pi Bond?
The formation of a pi bond takes place in a manner where it is formed by overlapping between two orbits in parallel or sideways. There is a high amount of energy emitted from this bond which makes it less stable. When it comes to participating in a Resonance without having to show its hyper- conjuration, that is when a pi bond comes into the picture.
In this kind of bond, there can be more than one pair of electrons between an atom which can move from one atom to another. This helps to make a Delocalized bond. Features like knowing how bond systems in a bond operate can be figured by all the single, double and triple bonds.
These bonds are very weak as they are bonded very loosely. The Pi bonds do not react that fast as compared to other bonds because of their characteristics of being a weak bond. This means no kind of symmetry exists between the Pi bonds. One important feature of a pi bond is that they always keep roaming behind the sigma bonds.
Main Differences Between Sigma Bond and Pi Bond
- A sigma bond is a strong bond as compared to a Pi bond, and on the other hand, a Pi bond is a weaker bond as compared to a Sigma bond.
- When an atom interacts, this is when a sigma bond is formed., and on the other hand, a pi bond forms when two atoms of sigma bonds are formed between them.
- When there is a bonding between two atoms, there can be only one sigma formed that is formed, and on the other hand, when there is a bonding between two atoms, there can be the existence of two pi bonds.
- A sigma bond in an atom is proved scientifically to be highly reactive by nature, and on the other hand, a Pi bond in an atom is said to be less reactive as compared to sigma bonds.
- Sigma bonds are bonds that exist independently and roam freely in orbit, and on the Other hand, pi bonds cannot roam freely and independently as they have a restricted rotation.
Conclusion
A chemical bond is distinguished into many times, such as the covalent bond and the polar bond. Two main chemical bonds are the Sigma bond and the Pi bond. Even though a sigma bond and pi bond emerge out of the same roots with some similarities in them, their vast differences cannot be ignored.
A sigma bond and a chemical bond have vast differences between them, which lie in how they are formed, how many atoms they require, how they move, and how they function. They have their difference in the characteristics and features that they possess. One should know the difference between a sigma bond and a pi bond.
References
- https://www.sciencedirect.com/science/article/pii/000926149285453H
- https://fens.ius.edu.ba/sites/default/files/u2578/organic_chemistry_ss2020_week1_and_2_intro_and_structure_of_organic_molecules_3.pdf