title: Car-Parrinello and path integral molecular dynamics study of the hydrogen bond in the chloroacetic acid dimer system.
abstract: We have studied the double proton transfer (DPT) reaction in the cyclic dimer of chloroacetic acid using both classical and path integral Car-Parrinello molecular dynamics. We also attempt to quantify the errors in the potential energy surface that arise from the use of a pure density functional. In the classical dynamics a clear reaction mechanism can be identified, where asynchronized DPT arises due to coupling between the O-H stretching oscillator and several low energy intermolecular vibrational modes. This mechanism is considerably altered when quantum tunneling is permitted in the simulation. The introduction of path integrals leads to considerable changes in the thermally averaged molecular geometry, leading to shorter and more centered hydrogen bond linkages.
authors: Faculty of Chemistry, University of Wroclaw, 14 F. Joliot-Curie, 50-383 Wroclaw, Poland.
authors: Piotr
authors: P
authors: Durlak
authors: Carole A
authors: CA
authors: Morrison
authors: Derek S
authors: DS
authors: Middlemiss
authors: Zdzislaw
authors: Z
authors: Latajka
mesh_terms: D000085:Acetates / Q000737:chemistry*; D002627:Chemistry, Physical / Q000379:methods*; D003198:Computer Simulation; D003903:Deuterium / Q000737:chemistry; D019281:Dimerization; D006860:Hydrogen Bonding; D008958:Models, Molecular; D015233:Models, Statistical; D008962:Models, Theoretical; D008968:Molecular Conformation; D009991:Oscillometry; D011789:Quantum Theory; D012984:Software; D013816:Thermodynamics; D013997:Time Factors
chemical_list: D000085:Acetates; C006972:chloroacetic acid; D003903:Deuterium