Are glycine cyclic dimers stable in aqueous solution?

Abstract

We have used ab initio molecular dynamics in an extensive study of the dynamics of glycine dimers in aqueous glycine solutions, investigating the effect of several variables, such as the presence of deuterated water or the presence of Cl⁻ and Na⁺ ions. Our simulations provide an atomistic insight into the processes of proton transfer between glycine and water molecules. They also confirm the findings of previous interatomic potentials-based molecular dynamics simulations, which suggest that glycine molecules do not form cyclic, doubly hydrogen bonded, dimers in aqueous solutions.