analyzing IR spectra

[aelek]

Hi everyone,

I'm analyzing these IR spectra and there are few things I'm uncertain about...

1-phenylethanol: I can't make out what are the two peaks at 14500 and 1500?

 

 

 

cyclohexanon: how to determine which of the two peaks (2938 or 2863) is due to C-H vibrations? or it's both of them?

 

 

 

benzoic acid: is there a way to determine which of the peaks ranging form 2560 to 3072 are due to OH vibrations, and which are due to aromatic ring CH stretching?

 

ps sorry about the poor quality of the images

[Elite Engineer]

1-phenylethanol spectra: When analyzing IR spectra, you typically dont need to pay attention to the fingerprint region (1400-600) for analysis. However, the peaks at 1450-1500 are identified as C-H scissoring and possibly some bending.

 

cyclohexanone spectra: Yes, the stretches at 2938 and 2863 are from C-H stretching.

 

benzoic acid spectra: The peak at 3072 is definitely an O-H stretch, however the rest I am not 100%, but would say they are most likely O-H, with maybe 2560 being a C-H stretch.

 

~ee

[aelek]

I know about the fingerprint region, I wasn't sure whether those peaks are actually in it, though (since those are ~14500 and 1500).

Thank you!