Computer Physics Communications Program LibraryPrograms in Physics & Physical Chemistry |

[Licence| Download | New Version Template] acye_v1_0.gz(81 Kbytes) | ||
---|---|---|

Manuscript Title: IMPACT: a program for the solution of the coupled integro-
differential equations of electron-atom collision theory. | ||

Authors: M.A. Crees, M.J. Seaton, P.M.H. Wilson | ||

Program title: IMPACT | ||

Catalogue identifier: ACYE_v1_0Distribution format: gz | ||

Journal reference: Comput. Phys. Commun. 15(1978)23 | ||

Programming language: Fortran. | ||

Computer: CDC 7600. | ||

Operating system: SCOPE 2.1.4. | ||

Program overlaid: yes | ||

RAM: 20K words | ||

Word size: 60 | ||

Peripherals: disc. | ||

Keywords: Atomic physics, Electron-atom, Electron-ion, Scattering. | ||

Classification: 2.4. | ||

Subprograms used: | ||

Cat
Id | Title | Reference |

ACYF_v1_0 | IMPPRO | CPC 15(1978)23 |

Other versions: | ||

Cat
Id | Title | Reference |

ACZK_v1_0 | ECSIMPACT | CPC 18(1979)287 |

Nature of problem:It is required to obtain approximate solutions of the Schroedinger equation (H-E)Psi=0 where Psi is the wave function for a system containing (M+1)-electrons and a nucleus of charge z. Using a variational principle, one obtains a system of coupled integro- differential (ID) equations for the radial functions F(r) and coefficients c. IMPACT is a computer program for the solution of these equations. Put E = ELOW + EKLSQ where ELOW is the energy for the ground state of the M electron system and EKLSQ is input to the program. For EKLSQ less than 0, IMPACT obtains approximate solutions of the Schroedinger equation for the bound state Psin of the (M+1) electron system with energy EN closest to ELOW + EKLSQ. For EKLSQ greater than 0, IMPACT solves the corresponding electron-atom or electron-ion collision problem. | ||

Solution method:The radial functions Fi(r) are tabulated at points r = R(1), R(2), ..., R(N), and matched to functions for r> R(N) obtained using a modified version of the program ASYM of Norcross. Using numerical methods, the ID equations are replaced by linear algebraic (LA) equations which are solved using standard techniques. | ||

Restrictions:The program IMPACT is provided in a form which must be pre-processed by a program IMPPRO, which inserts dimensions. Restrictions on the complexity of the problems which can be solved are determined entirely by available machine time and core store. |

Disclaimer | ScienceDirect | CPC Journal | CPC | QUB |