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[Licence| Download | New Version Template] adal_v2_0.gz(12 Kbytes)
Manuscript Title: DVR3D: a program suite for the calculation of rotation-vibration spectra of triatomic molecules (ROTLEV3).
Authors: J. Tennyson, M.A. Kostin, P. Barletta, G.J. Harris, O.L. Polyansky, J. Ramanlal, N.F. Zobov.
Program title: ROTLEV3
Catalogue identifier: ADAL_v2_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 163(2004)85
Programming language: Fortran 90.
Computer: PC, Compaq, Sunfire V750, V880, IBM p690, Origin 2000.
Operating system: UNIX, Linux, AIX.
RAM: Case dependent.
Keywords: Molecular spectra, Infrared, Microwave, Variational principle, Expectation values, Born-Oppenheimer approximation, Triatomic molecules.
PACS: 33.20, 39.30.
Classification: 16.3.

Subprograms used:
Cat Id Title Reference
ACNE_v3_0 DVR3DRJZ CPC 163(2004)85

Nature of problem:
ROTLEV3 performs the second step in a two-step variational calculation for the bound ro-vibrational levels of a triatomic system represented in either Jacobi or unsymmetrised Radau coordinates.

Solution method:
A basis is constructed from the solutions of the Coriolis decoupled problem provided by DVR3DRJZ. The angular coordinate is transformed back to a basis set representation. The sparse Hamiltonian matrix can be diagonalised iteratively or in core.

Restrictions:
The size of matrix that can practically be diagonalised.

Unusual features:
Most data is read directly from DVR3DRJZ. ROTLEV3 can provide data to drive DIPOLE3 and/or XPECT3.

Additional comments:
The code has been extensively vectorised. A parallel version of the code, PROTLEV3 has been developed [1], contact the first author for details.
ROTLEV3 forms part of the DVR3D suite of programs. The complete suite is catalogued under the identifier ADTI_v1_0. The tar.gz file for ADTI_v1_0 contains sample input and output data which can be used to test all the programs in the suite.

Running time:
Case dependent. The sample data takes less than a minute on a fast PC.

References:
[1] H.Y. Mussa and J. Tennyson, Computer Phys. Comms., 128, 434(2000).