Duo is a diatomic Fortran 2003 code code for solving a fully coupled rovibronic Schroedinger equation

The full documentation can be found here https://duo.readthedocs.io/en/latest/index.html

• 11.03.20023: New feature for selecting electronic states to be used in Duo calculations: States X, B, C, ....
• 12.02.2023: The diabatic and adiabatic options now give the same results (after some bugs fixed in the NAC section)!
• 07.02.2023: Reduced radial density is implemented as part of the checkpoint section. Can be activated using density save. It is cool!
• 18.02.2023: The dipole intensity calculations have been optimised; the half_linestrength subroutine openmp parallelised (most intensive part) and the print out of the Einstein A coefficients (.trans) is now done in batches, not lin-by-line.
• 16.02.2023: A problem in assign_by_count associated with the v=0 wrongly assigned at high J has been fixed.
• 12.02.2023: The definition of the nuclear spin (used for g_ns in intensity calculations) is now fully automatic using the nuclear spin data from the internal database. Specifying "nspin" or "gns" are not required anymore.
• A new keyword states_only in INTENSITY introduced used to generate .states file and skip .trans.
• 04.02.2023: New forms of PECs and DMCs are introduced: poten_EHH and dipole_medvedev_sing
• 02.01.2023: State labels (strings) can be used as state reference numbers. e.g. "potential A" or "spin-orbit A C"
• 02.01.2023: Finding crossing point between two diabatic states and using it as an expansion centre.
• 02.01.2023: relation between abinitio fields and their parent fields has been refactored to make it more stable when using in the fitting
• 17.07.2022: bound/continuum state treatment is introduced: with "bound" and "unbound" in INTENSITY compute intensities for bound and continuum spectra.