Strong intramolecular hydrogen bonding in confined amino acids

Intramolecular hydrogen bonding is evaluated in three different amino acids encapsulated in C60 fullerene in the context of electron density analysis. While conventional intramolecular hydrogen bonding in isolated amino acids are dominated by electrostatic character, it is shown that strong intramolecular hydrogen bonding can be formed in confined amino acids so that in two cases covalent intramolecular hydrogen bonding is appeared in the...