Program dPotFit16

dPotFit16 is R.J. Le Roy's program for performing least-squares fits of a diatomic molecule data set involving one or more singlet, or doublet-Sigma electronic states, and one or more isotopomers, to parameters defining analytic potential energy functions for each state. These potentials may have a variety of functional forms, and the fits may allow for potential-energy or centrifugal Born-Oppenheimer breakdown (BOB) corection functions to be included. The data set may consist of any combination of microwave, infrared or electronic band data, fluorescence series, binding energies from photoassociation spectroscopy, tunneling predissociation level widths, and ab initio potential energy function or virial coefficient values.

A full description of the most recent version of this code has been published online in J. Quant. Spectrosc. Radiat. Transfer 186, 179 (2016), which is available at, while the corresponding source code and detailed Program Manual are available as Supplementary "Application" files at that www link. All future citations regarding use of this code should refer to this Journal Article,

A new beta version of this code that is accessible to University of Waterloo users includes a number of specialized enhancements currently under development, and is described by the modified write-up and manual dPotfit17 Manual. Noteworthy changes in this version are the introduction of a third type of damping function, the new (simpler!) Eq.(13), modifications in the manner in which the integer powers q and p defining the dimensionless radial variables of Eqs.(5) and (6) are read in (see READS #21-23), and the option for imposing a constraining relationship on the long-range Cm coefficients for different electronic states (see description of READs #16 and 17).

If you wish to be Registered with the author as a user of this code, eligible to be sent any future bug fixes or updates, please fill in the following form Register dPotFit-16 Registration. Note that the ordering of the parameter in data input Lines No. 20, 23 and 30, and the definitions of some of the parameters in input data Line 20, have been changed from those in earlier versions of this code. In addition, this new version uses the 2010 values of ħ, and its atomic masses subroutine incorporates the 2012 version of the atomic mass table.
As ever, I would be pleased to receive information regarding apparent or real malfunctions of this code or weakness in the documentation, please contact the author by e-mail: 'leroy AT'

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