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Why can hydrogen bonding occur with nitrogen, oxygen, and fluorine?

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A rough, translucent yellow crystal of elemental sulfur displayed against a solid black background. — crystal A crystal form of elemental sulfur. Sulfur has an atomic weight of about 32.06 atomic mass units (amu), which means that its molar mass is 32.06 grams.

Hydrogen bonding occurs specifically with nitrogen, oxygen, and fluorine because these elements are highly electronegative and small in size.51

When a hydrogen atom is covalently bonded to one of these atoms, the electronegative atom pulls the shared electron pair toward itself, creating a significant partial positive charge on the hydrogen and a partial negative charge on the donor atom. Because the hydrogen atom is very small, it can approach these electronegative atoms closely, allowing for a strong electrostatic attraction between the partially positive hydrogen and the unshared electron pair of a neighboring electronegative atom.234

In this interaction, the hydrogen atom effectively acts as a bridge between two electronegative atoms. The small size of the hydrogen atom is critical, as it enables a favorable balance of energies in the molecular orbital scheme, which facilitates this specific type of bonding. While other atoms can participate in hydrogen bonding if they are sufficiently electron-rich and negatively charged, the unique combination of high electronegativity and small atomic radius makes nitrogen, oxygen, and fluorine the primary participants in these interactions.514