# How to predict the frequency of NMR spectrum

#### SqrachMasda

I have a molecule and I'm barely accostumed to H-NMR and C-NMR
this has neither
it's trifluorophosphine
I have to predict the splitting, intensities and frequency
the first two I think I have some idea about
but I don't even know where to look on how I could calculate this
it seems like if you can calculate all this without an NMR, would that make these million dollar instruments a bit insignificant
probably not

is this possible
where can I find info on it
there's nothing with it but the molecule and I am not sure if there is some kind of information I would need in order to find it
or is it just something I have to find from a a list of pre established values?

thanks
sorry for rambling

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#### DrClaude

Mentor
This would have to be $^{31}$P-NMR. One could estimate the chemical shift and intensities by comparing to the NMR of similar molecules. Splittings can be found by considering spin-spin coupling.

But generally speaking, a relatively accurate prediction of a NMR spectrum can only be obtained by quantum chemistry calculations.

"How to predict the frequency of NMR spectrum"

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