Usually first the C-H vibrations are identified (aliphatic/aromatic) and the presence of OH and/or NH groups are checked. The presence of cumulated double bonds or triple bonds can be observed easily between 2000 and 2500 1/cm. The next important area is that of double bonds, esepcially carbonyls. C-O bonds can also be identified relatively easily. The rest is minute work requiring tables, databases and a lot of epxrience. If you have any idea of the compound, comparison with literature spectra may help. If you have a mixture, it helps a lot if you can take the spectra of the components. There are several good books and websites for this purpose.

Usually first the C-H vibrations are identified (aliphatic/aromatic) and the presence of OH and/or NH groups are checked. The presence of cumulated double bonds or triple bonds can be observed easily between 2000 and 2500 1/cm. The next important area is that of double bonds, esepcially carbonyls. C-O bonds can also be identified relatively easily. The rest is minute work requiring tables, databases and a lot of epxrience. If you have any idea of the compound, comparison with literature spectra may help. If you have a mixture, it helps a lot if you can take the spectra of the components. There are several good books and websites for this purpose.

I used the IRIS free software available in the website.It was quite useful.

But discussions with eminent scholars will help

Infrared and Raman characteristic group frequencies from G. Socrates. Depends on the kind of the material (organic/inorganic). Although a lot of information is present on the internet. Check the SDBS website for individual IR spectra of products

I very much like the tables/assignments of the book

... structure analysis organic compounds ...

Pretsch Clerc Seibl Simon

Springer

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