Molecular Dynamics Seminars 2012 - Rainer Böckmann: "Membrane molecular dynamics force fields"
von 16:15 bis 17:00
|Wo||Seminar Room of Gustav Mie Haus, Ground Floor|
|Kontakttelefon||+49 (0)761-203 97336|
Open to University employees
Molecular Dynamics Seminars 2012
is initiated by Institute of Physics, University of Freiburg and FRIAS.
For further information:
Membrane molecular dynamics force fields
The all-atom optimized potentials for liquid simulations (OPLS-AA) force field is a popular force field for simulating biomolecules. Here, we optimized the OPLS-AA force field for both short and long hydrocarbons, as well as for phospholipids. Following the framework of the OPLS-AA parametrization, we refined the torsional parameters for hydrocarbons by fitting to the gas-phase ab initio energy profiles calculated at the accurate MP2/aug-ccpVTZ theory level. Additionally, the Lennard-Jones potential was adjusted to reproduce the densities and the heats of vaporization of alkanes and alkenes of different lengths. Optimization of partial charges finally allowed to reproduce the gel-to-liquid-phase transition temperature for pentadecane. It is shown that the optimized parameter set (LOPLS) yields improved hydrocarbon diffusion coefficients, viscosities, and gauche-trans ratios. In a second step, L-OPLS was extended to cover frequent phospholipids. Its applicability for lipid bilayer simulations is shown for various phospholipid bilayers.