WATERWAVES: wave particles dynamics on a complex triatomic potential

The WATERWAVES program suite performs complex scattering calculations by propagating a wave packet in a complex, full-dimensional potential for non-rotating (J=0J=0) but vibrating triatomic molecules. Potential energy and decay probability surfaces must be provided. 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. The bottleneck of the calculation is the application of each term of the Hamiltonian to the wave packet. To solve this problem the programs use a different representation for each term: normalized associated Legendre polynomials PjK(x) as a functional basis for the angular kinetic term and an evenly spaced grid for the radial kinetic term yielding a fully point-wise representation of the wave functions. The potential term is treated using an efficient Discrete Variable Representation (DVR) being diagonal in the coordinate representation. The radial kinetic term uses a fast Fourier transform (FFT) to obtain an operator which is diagonal in the momentum space. 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.Program summaryProgram title: WATERWAVESCatalogue identifier:ADXT_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXT_v1_0Program obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandLicensing provisions: Freely available from CPCProgramming language: Fortran 77Computer(s) for which the program has been designed: PCOperating system(s) for which the program has been designed: LinuxRAM required to execute with typical data: case dependent: test run requires 976 024 kBNo. of bytes in distributed program, including test data, etc.:11 262 681No. of lines in distributed program, including test data, etc.:2 510 113Distribution format:tar.gzNumber of processors used: 1External routines/libraries used: NoneCPC Program Library subprograms used: NoneNature 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=0J=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: Program asymptot.f for analysing results, 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 2 060 044 kB of memory.