Shapes of Orbitals and Bonds

The overlap represents a space where the shared electrons spend a lot of time, so it has increased negativity and holds the two positive nuclei together in their appropriate positions. When orbitals have a good overlap, the covalent bonding is called a sigma ( ) bond. 

The coverage of covalent bonding and overlap of orbitals is a study in its own right. To go further with this topic, you might like to read a more advanced text and consider the topic of hybridisation . 

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