1. Infrared Spectroscopy

2. Electromagnetic radiation Ultraviolet –190 nm to 400 nm –Electronic transitions  to  *  to  * Visible –400 nm to 700 nm –Electronic transitions involving molecular orbitals

3. Electromagnetic Radiation Infrared –800 nm to 2500 nm Near infrared –2500 nm (4000 cm -1 ) to 15000 nm (667 cm -1 ) Ordinary infrared –15000 nm to 200000 nm Far infrared

4. Energy and vibrations Energy is measured in cm-1 –4000 cm -1 is the high energy end and 667 cm -1 is the low energy end. Vibrations –Stretching (require higher energy) –Bending (normally involve several bonds) –C=C at higher energy than C-C

5. Nonane C-H stretch and C-H bends C-H stretch, sp 3 CH 2 bend CH 3 bend

6. 1-Octene C-H stretch, C=C stretch, CH bend sp 2 CH str sp 3 CH str C=C str CH bends

7. 1-Octyne CH stretch, C≡C stretch sp CH str C≡C str CO 2

8. m-Xylene Aromatic peaks CH > 3000 650-800 2000-1667 1600,1500

9. Phenanthrene Aromatic peaks CH > 3000 and 650-800 cm -1

10. 1-Pentanol OH stretch, CH stretch, CH bend, CO stretch C-O str, 1000-1200

11. 2-Butanol OH stretch, CH stretch, CH bend, CO stretch

12. 4-Methyl-2-pentanone CH stretch, C=O stretch C=O str

13. 4-Methylacetophenone CH stretch, C=O stretch C=O < 1700, conjugated

14. Pentanal CH and CHO stretches, C=O stretch Water C=O stretch

15. Benzaldehyde CH and CHO stretches, C=O stretch, aromatic peaks C=O str < 1700 CHO stretches

16. Hexanoic acid OH stretch and C=O stretch C=O str OH stretch

17. Ethyl benzoate CH stretch, C=O and C-O stretches C=O str, 1725 cm -1 C-O stretch

18. Isobutyl amine NH stretch, NH bend

19. Diisopropyl amine NH stretch, NH bend

20. Methyl formamide NH stretch, C=O stretch

21. Benzonitrile CN stretch Aromatic C≡N stretch

22. Nitrobenzene NO stretches (asymmetric and symmetric) NO stretch

23. The Nicolet Infrared