Magnetic Transition State Searching: Beyond the Static Ion Approximation

Beyond the perturbed static path approximation (PSPA)

Based on the path integral approach the partition function of a many body system with separable two body interaction is calculated in the sense of a semiclassical approximation. The commonly used Gaussian type of approximation, known as the perturbed static path approximation (PSPA), breaks down near a crossover temperature due to instabilities of the classical mean field solution. It is shown ...

The nucleon-nucleon potential beyond the static approximation

Deptartament d’Estructura i Constituents de la Matèria, Universitat de Barcelona Diagonal 647, 08028 Barcelona, Catalonia, Spain Abstract We point out that, due to the use of static nucleon propagators in Heavy Baryon Chiral Perturbation Theory, the current calculations of the nucleon-nucleon potential miss certain contributions starting at two loops. These contributions give rise to contact in...

Beyond the rigid-ion approximation with spherically symmetric ions.

Relativistic Two-body Bound-state Calculations beyond the Ladder Approximation

In this work the Feynman-Schwinger representation for the two-body Greens function is studied. After having given a brief introduction to the formalism, we report on the first calculations based on this formalism. In order to demonstrate the validity of the method, we consider the static case where the mass of one of the particles becomes very large. We show that the heavy particle follows a cl...

Large-Scale Density Functional Theory Transition State Searching in Enzymes.

Linear-scaling quantum mechanical density functional theory calculations have been applied to study the rearrangement of chorismate to prephenate in large-scale models of the Bacillus subtilis chorismate mutase enzyme. By treating up to 2000 atoms at a consistent quantum mechanical level of theory, we obtain an unbiased, almost parameter-free description of the transition state geometry and ene...