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Manuscript Title: DVR3D: a program suite for the calculation of rotation-vibration spectra of triatomic molecules (XPECT3).
Authors: J. Tennyson, M.A. Kostin, P. Barletta, G.J. Harris, O.L. Polyansky, J. Ramanlal, N.F. Zobov.
Program title: XPECT3
Catalogue identifier: ADTH
Journal reference: Comput. Phys. Commun. 163(2004)85
Programming language: Fortran 90.
Computer: PC, Sunfire V750, V880, Compaq, IBM p690, Origin 2000.
Operating system: UNIX, Linux, AIX.
RAM: Case dependent.
Keywords: Expectation values, Hellmann-Feynman theorem, potential fitting.
PACS: 33.20, 39.30.
Classification: 16.3.

Subprograms used:
Cat Id Title Reference
ADTB DVR3DRJZ CPC 163(2004)85
ADTC ROTLEV3 CPC 163(2004)85
ADTD ROTLEV3B CPC 163(2004)85
ADTE ROTLEV3Z CPC 163(2004)85
ADTF DIPOLE3 CPC 163(2004)85
ADTG SPECTRA CPC 163(2004)85

Nature of problem:
XPECT3 calculates expectation of geometrically defined operators using previously calculated wavefunctions.

Solution method:
Integrals over the user defined surfaces are constructed using a DVR in all three coordinates. Wavefunctions generated by DVR3DRJZ and ROTLEV3 or ROTLEV3b are then used to give expectation values for each state.

The complexity of the problem that can be solved by DVR3DRJZ, ROTLEV3 or ROTLEV3B.

Unusual features:
Most data is read directly from DVR3DRJZ and ROTLEV3 or ROTLEV3B.

Additional comments:
The code has been extensively vectorised. Commands to parallelise the code using OpenMP are included in the source.
XPECT3 forms part of the DVR3D suite of programs. The complete suite is catalogued under the identifier ADTI. The tar.gz file for ADTI contains sample input and output data which can be used to test all the programs in the suite.

Running time:
Case dependent. The test data takes a few seconds on a fast PC.