A multicanonical ab initio molecular dynamics method: Application to conformation sampling of alanine tripeptide

We propose a multicanonical ab initio molecular dynamics (AIMD) method for enhanced conformation sampling of biomolecules. This method was applied to a blocked alanine peptide, Ace-(Ala)2-NMe, and was proved to be more efficient in conformation sampling than a conventional AIMD method. This figure shows the free-energy landscape of the backbone ϕ-ψ dihedral angles of the first alanine in the canonical ensemble at 300 K obtained from the simulation.