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I am trying to interpret an IR spectrum where I have $\ce{(NPCl2)3}$

I have $\ce{P-N}$, $\ce{P=N}$ and $\ce{P-Cl}$ bonds and it is cyclic.

Where can I find or does anyone know what the general ranges for these stretches are?

I found a website that told me $\ce{P=N}$ is around $1170 \, \mathrm{cm}^{-1}$.

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A good resource for IR and Raman bands is "Infrared and Raman Characteristic Group Frequencies: Tables and Charts" by George Socrates. There you can find a chart containing the positions and intensities of bands observed in the infrared spectra of phosphorus compounds (explanation: "w", "m", "s" specify the observed intensity of the bands means whereby "w" stands for "weak", "m" for "medium", and "s" for "strong"; additionally the prefix "v" can be given meaning "very", e.g. "vs" means "very strong"):

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More specifically you find the following numbers for the different bands you are looking for:

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There is also another comment on $\ce{P-Cl}$ bands:

Compounds containing the $\ce{P-Cl}$ bond have a medium-to-strong absorption at $605 - 435$ $\mathrm{cm}^{-1}$ due to the $\ce{P-Cl}$ stretching vibration. The position of the band due to the $\ce{P-X}$ ($\ce{X}$=$\ce{F}$ or $\ce{Cl}$) stretching vibration is affected by the oxidation state of the phosphorus atom. 'In the presence of more than one halogen atom directly attached to the phosphorus atom, two peaks are observed due to the asymmetric and symmetric stretching vibrations respectively. Difluorides of the type $\ce{-P(O)F2}$ absorb at $930-895$ $\mathrm{cm}^{-1}$ and $890-870$ $\mathrm{cm}^{-1}$

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