Methyl — FTIR absorption peaks and assignments

Quick answer

Methyl is usually assigned by looking for a recurring cluster of characteristic peaks rather than one exact textbook number. The table below shows where the literature most often places this group in FTIR, ranked by accumulated evidence.

Characteristic FTIR peaks for Methyl

Showing the 30 best-supported peaks of 463 total for Methyl.

Spectrum logic

A functional-group assignment becomes more confident when several expected bands appear together. Use this page to find the strongest-supported peaks, then confirm that the same sample exhibits a coherent pattern rather than a single isolated hit.

Real-world usage

These pages are useful for unknown material analysis, peak explanation in reports, polymer troubleshooting, and verifying whether a candidate material family is chemically plausible.

Common mistakes

• Using one functional-group page as a complete material verdict without checking the rest of the spectrum.
• Assuming the strongest band is always the most diagnostic one.
• Forgetting that processing, additives, aging, and mixtures can shift or broaden expected peaks.

Verification advice

Use DSC, GC-MS, or TGA when several material families share similar bands or when mixture effects make the FTIR assignment uncertain.

Literature behind these assignments

• 2927 cm⁻¹ confidence 1.0

  “The stretching of hydroxyl group (─OH) of starch was presented by a peak at 3291 cm-1 whereas the starch methyl group at 3291cm-1 2927 cm-1.”

  Ashri 等 - 2018 - Modified Dioscorea hispida starch-based hydrogels DOI: 10.1016/j.ijbiomac.2017.10.125
• 1142 cm⁻¹ confidence 1.0

  “42 43 cm-1 In the spectrum of PMMA, there is a distinct absorption band at 1142 which is due to O-CH 3 44”

  Ataei 等 - 2020 - Electrosprayed PMMA microcapsules containing green DOI: 10.1088/1361-665X/ab9754
• 1420 cm⁻¹ confidence 1.0

  “Only the green group cm-1 showed to have peak located at ~1420 which is assigned for C-H bending of methyl, and”

  Azlah 等 - 2020 - A fast and reliable 2D-IR spectroscopic technique DOI: 10.1016/j.vibspec.2019.103014
• 2920 cm⁻¹ confidence 1.0

  “cm-1 compounds remained The peaks at 2920 and 2840 correspond to C-H stretching of methyl and methylene62.”

  Physicochemical characterisation of barley straw treated with sodium hydroxide or urea and its digestibility and in vitro fermentability in ruminants DOI: 10.1038/s41598-022-24738-w
• 1509 cm⁻¹ confidence 1.0

  “In both cases the characteristic absorption bands are showed: 1509 and 1608 cm-1 (C=C bonds of aromatic ring), 1457 cm-1 (CH2 group vibration), 1362 cm-1 (methyl group vibration) and”

  Barbadillo 等 - 2003 - Study of a curing reaction of an epoxy resin DOI: 10.4028/www.scientific.net/MSF.426-432.2163
• 1234 cm⁻¹ confidence 1.0

  “C-O-C stretching in esters 1234 (w) 1232 (w) 1242 (w) CH3 bending 1379 (w)”

  Barnaby 等 - 2018 - Free Radical Scavenging Capacity, Carotenoid Conte DOI: 10.1155/2018/1762342
• 1264 cm⁻¹ confidence 1.0

  “The peak at 1264 Phytonanocomposite indicates the presence of strong methyl bond.”

  Synthesis of Phytonanocomposite of Zinc Oxide by Ixora coccinea Linn for Cancer Treatment DOI: 10.1007/s10904-016-0382-y
• 500 cm⁻¹ confidence 1.0

  “The exothermic peak at 500 by hydrolytically stable -Si-(CH 3) groups present in HMDS corresponds to the critical temperature of -(CH 3) groups at 3 3 and TMCS, according to the chemical reactions (2) and (3) which they get oxidized leaving”

  Bhagat 等 - 2007 - Rapid synthesis of water-glass based aerogels by i DOI: 10.1016/j.apsusc.2006.07.016