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Electron scattering by closed or open shell diatomic molecules
C-636 Computer Physics Communications 20 (1980) 275-289 © North-Holland Publishing Company
E L E C T R O N S C A T T E R I N G BY C L O S E D O R O P E N S H E L L D I A T O M I C M O L E C U L E S G. R A ~ E E V "
Centre de M~canique Ondulatoire Appliqude, 23, rue du Maroc, 75019 Paris, France Received 23 May 1979
PROGRAM SUMMARY
Title o f the program: ELECTRON MOLECULE SCATTERING Catalogue number: ACZS Computer: IBM 370/168; Installation: Centre Inter Rdgional de Calcul Electronique, Bgtiment 506, Campus d'Orsay, 91405 Orsay, France and Computer: IBM 370/158; Installation: Universit6 de Liege Operating system: JES 3 and ASP Program language: FORTRAN IV High speed storage requested: with the test deck data: 640 Kwords Number o f bits in a word: 32 Overlay structure: none Number of files requested: 4 or 5 Other peripherals used: card reader, card punch, line printer Number o f cards in combined program and test deck: 10 926
The final continuum wave function is also calculated and stored on f'fle.
Method o f solution The approach is based on a single-centre expansion of the molecular and incident electron orbitals. This centre can be any point for example the centre of mass, one of the atoms or the centre of charge of the molecule. The target molecule is represented by a LCAO-MO-SCF wave function which can be of closed or restricted open-sheU type. It is assumed that the molecular axis does not rotate during the collision. The coupled integro-differential equations, with an orthogonalisation constraint and a modified exchange function (Raseev et al. 121) are solved by a method analogous to the electron atom case [3 l-
CPC library subprogram required/for data] : Cat. no. : ACZR; Title: ONE CENTRE STATIC POTENTIAL; Ref. in CPC: 20 (1980) 000 Reference to other published version o f this program: Cat. no.: ACQO; title: ELECTRON MOLECULE SCATTERING; Ref. in CPC: 1 (1970)445. Keywords: quantum chemistry, electron scattering, open
Restrictions on the complexity o f the problem
shells, single centre expansion, continuum Hartree-Fock, elastic cross sections
The test run of CH( 2 X+(l Fl + e(rr))) with 200 mesh points which is about a half of the standard value requires about 23 s on an IBM 370]168. This test uses a five-term potential, has 6 compact exchange functions and performs the orthogonalisation with a l~r orbital.
Nature of the physical problem An extension of the existing low-energy electron diatomic scattering program [ 1 ] to open-shell molecular targets is presented. In this version, the orthogonalisation between bound and continuum orbitals is introduced. The K matrix elements and the eigen-phases for rotational excitation are evaluated.
The program written in FORTRAN is dynamically allocated by an interface written in assembler (370/168). This interface can be replaced by a small FORTRAN main program provided with the program.
Typical running time
References [ 11 A.L. Sinfailam, Comput. Phys. Commun. 1 (1970) 445. [2] G. Ra~eev, A. Giusti-Suzor and H. Lef~bvre-Brion, J. Phys. B 11 (1978) 2735. [3] P.G. Burke and M.J. Seaton, Methods Comput. Phys. 10 (1971) 1.
Present address: Laboratoire de Chimie G6ndrale et Physique, B,~timent B.6, Universit6 de Liege, B-4000 Sart-Tilman par Lidge 1, Belgium.
E L E C T R O N S C A T T E R I N G BY C L O S E D O R O P E N S H E L L D I A T O M I C M O L E C U L E S G. R A ~ E E V "
Centre de M~canique Ondulatoire Appliqude, 23, rue du Maroc, 75019 Paris, France Received 23 May 1979
PROGRAM SUMMARY
Title o f the program: ELECTRON MOLECULE SCATTERING Catalogue number: ACZS Computer: IBM 370/168; Installation: Centre Inter Rdgional de Calcul Electronique, Bgtiment 506, Campus d'Orsay, 91405 Orsay, France and Computer: IBM 370/158; Installation: Universit6 de Liege Operating system: JES 3 and ASP Program language: FORTRAN IV High speed storage requested: with the test deck data: 640 Kwords Number o f bits in a word: 32 Overlay structure: none Number of files requested: 4 or 5 Other peripherals used: card reader, card punch, line printer Number o f cards in combined program and test deck: 10 926
The final continuum wave function is also calculated and stored on f'fle.
Method o f solution The approach is based on a single-centre expansion of the molecular and incident electron orbitals. This centre can be any point for example the centre of mass, one of the atoms or the centre of charge of the molecule. The target molecule is represented by a LCAO-MO-SCF wave function which can be of closed or restricted open-sheU type. It is assumed that the molecular axis does not rotate during the collision. The coupled integro-differential equations, with an orthogonalisation constraint and a modified exchange function (Raseev et al. 121) are solved by a method analogous to the electron atom case [3 l-
CPC library subprogram required/for data] : Cat. no. : ACZR; Title: ONE CENTRE STATIC POTENTIAL; Ref. in CPC: 20 (1980) 000 Reference to other published version o f this program: Cat. no.: ACQO; title: ELECTRON MOLECULE SCATTERING; Ref. in CPC: 1 (1970)445. Keywords: quantum chemistry, electron scattering, open
Restrictions on the complexity o f the problem
shells, single centre expansion, continuum Hartree-Fock, elastic cross sections
The test run of CH( 2 X+(l Fl + e(rr))) with 200 mesh points which is about a half of the standard value requires about 23 s on an IBM 370]168. This test uses a five-term potential, has 6 compact exchange functions and performs the orthogonalisation with a l~r orbital.
Nature of the physical problem An extension of the existing low-energy electron diatomic scattering program [ 1 ] to open-shell molecular targets is presented. In this version, the orthogonalisation between bound and continuum orbitals is introduced. The K matrix elements and the eigen-phases for rotational excitation are evaluated.
The program written in FORTRAN is dynamically allocated by an interface written in assembler (370/168). This interface can be replaced by a small FORTRAN main program provided with the program.
Typical running time
References [ 11 A.L. Sinfailam, Comput. Phys. Commun. 1 (1970) 445. [2] G. Ra~eev, A. Giusti-Suzor and H. Lef~bvre-Brion, J. Phys. B 11 (1978) 2735. [3] P.G. Burke and M.J. Seaton, Methods Comput. Phys. 10 (1971) 1.
Present address: Laboratoire de Chimie G6ndrale et Physique, B,~timent B.6, Universit6 de Liege, B-4000 Sart-Tilman par Lidge 1, Belgium.