title: Mixed quantum-classical simulations of the vibrational relaxation of photolyzed carbon monoxide in a hemoprotein.
abstract: We present mixed quantum-classical simulations on relaxation and dephasing of vibrationally excited carbon monoxide within a protein environment. The methodology is based on a vibrational surface hopping approach treating the vibrational states of CO quantum mechanically, while all remaining degrees of freedom are described by means of classical molecular dynamics. The CO vibrational states form the "surfaces" for the classical trajectories of protein and solvent atoms. In return, environmentally induced non-adiabatic couplings between these states cause transitions describing the vibrational relaxation from first principles. The molecular dynamics simulation yields a detailed atomistic picture of the energy relaxation pathways, taking the molecular structure and dynamics of the protein and its solvent fully into account. Using the ultrafast photolysis of CO in the hemoprotein FixL as an example, we study the relaxation of vibrationally excited CO and evaluate the role of each of the FixL residues forming the heme pocket.
authors: Laboratoire Collisions Agrégats et Réactivité, IRSAMC, UMR CNRS 5589, Université Paul Sabatier, 31062 Toulouse, France.
authors: Alexander
authors: A
authors: Schubert
authors: Institut des Sciences Moléculaires d'Orsay (ISMO), CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91405 Orsay, France.
authors: Cyril
authors: C
authors: Falvo
authors: Laboratoire Collisions Agrégats et Réactivité, IRSAMC, UMR CNRS 5589, Université Paul Sabatier, 31062 Toulouse, France.
authors: Christoph
authors: C
authors: Meier
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D002248:Carbon Monoxide / Q000737:chemistry*; D006420:Hemeproteins / Q000737:chemistry*; D000071677:Histidine Kinase; D056004:Molecular Dynamics Simulation; D010782:Photolysis; D011789:Quantum Theory; D014732:Vibration
chemical_list: D001426:Bacterial Proteins; D006420:Hemeproteins; D002248:Carbon Monoxide; C067929:FixL protein, Bacteria; D000071677:Histidine Kinase