|This program calculates 3JHH values
according to Haasnoot et al.. Since the equation depends
on the relative orientation of the substituents a molecular model
will be of help. Turn the model so that the proton on the near
side is pointing up then use the schemes below to determine the
numbering of the substituents (e.g. S1, S2
etc.) and select the appropriate elements from the menus.
The program will automatically select to correct equation (C,
D, or E) depending on the number of attached hydrogens.
(Lit: "The relationship between proton-proton nmr coupling constants
and substituent electronegativities-I"
C.A.G. Haasnoot, F.A.A.M. DeLeeuw and C. Altona