IR Spectroscopy Numbers

IR spectroscopy flashcards focusing on key absorption numbers and corresponding molecular motions.

~3000 cm-1

O-H and N-H stretches (broad and strong). C-H stretches (strong and sharp) also occur here but are less diagnostically helpful.

~2000 cm-1

Terminal alkyne and cyano triple bond stretches (sharp and weak)

~1700 cm-1

Carbonyl C=O double bond stretches (sharp and strong). Acyl halides appear at the high end (1780-1800 cm-1) and amides at the low end (1680 cm-1)

~1600 cm-1

Alkene C=C double bond stretches (sharp and medium to weak)

Below 1500 cm-1: fingerprint region

Unique to each compound.