dParFit16 is R.J. Le Roy's program for performing least-squares fits
of a diatomic molecule spectroscopic data set consisting of any combination
of microwave, infrared or electronic vibrational bands, fluorescence series,
photo-association spectroscopy binding energies and/or input Bv
values, involving one or more singlet electronic states and one or more
isotopomers, to parameters defining the energy levels of each state.
The levels for each electronic state may be described by one of:
and the effect of lambda doubling or doublet-sigma spin splitting is
represented either by band-type constants for each vibrational level
of each isotopomer, or by Dunham-type expansions in (v+1/2). Dunham,
pure NDE or MXS fits automatically incorporate normal first-order
semiclassical multi-isotopomer mass scaling, and allow for inclusion of
atomic-mass-dependent Born-Oppenheimer and first-order JWKB breakdown
corrections (collectively called BOB corrections) for each electronic state.
A full description of the most recent version of this code has been published
online in J. Quant. Spectrosc. Radiat. Transfer 186, 197 (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.
band constants Gv, Bv, Dv, ... etc.
for each vibrational level of each isotopomer,
generalized Dunham expansions,
near-dissociation expansions (NDE), or
mixed NDE/Dunham functions (MXS), or
independent term values for each vibration-rotation level of each
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 dParFit-16 Registration. Note that the only non-cosmetic
change from the most recent previous versions of this code are that the
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 uwaterloo.ca'
Site owned by R.J. Le Roy, leroy AT uwaterloo.ca.
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