| Wavenumber (cm−1) | Assignment |
| 3585 | O?H stretching in acetic acid/CO2 gas |
| 3478 - 3373 | O?H stretching in water |
| 3000 [18] | CH3 asymmetric stretch in acetone |
| 2989, 2942 | C?H stretching in methyl |
| 2360 | CO2 gas |
| 1715 [19] | C=O stretching in acetone |
| 1722 [20] | C=O stretching in acetic acid |
| 1608 | C=O asymmetric stretching |
| 1620 | O-H in H2O, |
| 1613 [21] | Cu?H stretching in CH3-CuH− |
| 1580 - 1550 | C=O asymmetric stretching |
| 1573 [20] | O-H stretching in chemisorbed H2O |
| 1450 - 1430 | C=O symmetric stretching |
| 1375 (1362) [20] | C=O symmetric stretching |
| 1355 | C?H bending in methyl |
| 1243 [20] | C-OH stretching in acetic acid |
| 1203 [21] | CH3-Cu, CH3 deform |
| 1051 - 1033 | C?CH framework vibration |
| 944 | C?O stretching in acetic acid |
| 1012 [21] | CH3-CuH, CH3 deform |
| 668 - 682 | CO2 gas |
| 648 [21] | CH3-Cu, CH3 rock |