PHYS 529 |
| In using the diffusion quantum Monte Carlo method to solve the Schrödinger equation for a system, a time step error is introduced due to not being able to take infinitely small steps in the calculation. Studies of the free rigid rotor indicate that the calculated energy levels in multiples of the rotational constant (B) are controlled by (h/2π)*Δt/B. Using a Green's function numerical method with the second order short-time propagator, we investigate the behavior of the time step error in three rigid rotor systems: a rigid rotor in a Stark field, a model for a homonuclear diatomic in an external electric field, and a simple model for rotational-translational coupling of a rigid rotor trapped in a substitutional site in a cryogenic rare gas matrix. |
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PHYS Poster Session - General Theory
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster
Division of Physical Chemistry |