Computer Physics Communications Program Library

Programs in Physics & Physical Chemistry



Manuscript Title: WATERWAVES: wave particles dynamics on a complex triatomic potential
Authors: Simone Taioli, Jonathan Tennyson
Program title: WATERWAVES
Catalogue identifier: ADXT_v1_0 Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 175(2006)41
Programming language: Fortran 77.
Computer: PC.
Operating system: Linux.
RAM: case dependent; test run requires 976024 kBytes.
Keywords: Wavepacket, Jacobi coordinates, absorbing potential, expectation values, local complex potential approximation, triatomic molecules, asymptotic analysis.
PACS: 33.20, 39.30, 34.80 Ht.
Classification: 16.5.
Nature of problem: The WATERWAVES program suite performs complex scattering calculations for calculating the nuclear dynamics subsequent to excitation by, for example, electron or photon impact and leading to dissociative attachment or vibrational excitation. This program treats in a fully multidimensional way the nuclear motion based on the use of complex potential surfaces of three-atom systems. Complex potential energy surfaces have to be provided from fixed-nuclei calculations.
Solution method: By propagating a wave packet in a complex, full-dimensional potential for non-rotating (J=0) but vibrating triatomic molecules, expectation values of geometric quantities can be calculated, which are useful for following the wave packet motion. The programs use a local complex potential approximation (LCP) for the Hamiltonian and Jacobi coordinates. Potential energy and decay probability surfaces must be provided. To solve this problem the programs use a different representation for each term. To avoid artificial reflection at the boundaries of the grid a complex absorbing potential is included for calculating continuum quantities. Asymptotic analysis is performed to obtain scattering observables such as cross sections and other dynamical properties.
Additional comments: The distribution contains, the program asymptot.f for analysing results and test data and shell scripts to make a movie of the results.
Running time: case dependent: test run requires about 200 minutes on a 3.00 GHz Intel Pentium 4 machine provided with 2060044 kB of memory.