S eq o — FTIR absorption peaks and assignments

Quick answer

S eq o 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 S eq o

Showing the 30 best-supported peaks of 184 total for S eq o.

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

• 1255 cm⁻¹ confidence 1.0

  “OH group 1593 CH bending 1240 S=O stretching 1255”

  Artemisia 等 - 2019 - The Properties of Brown Marine Algae Sargassum tur DOI: 10.14499/indonesianjpharm30iss1pp43
• 1035 cm⁻¹ confidence 1.0

  “FTIR showed peak at 26 cm-1 1035 which corresponded to O=S=O stretching of sulphonic (-SO 3H) group.”

  Balan 等 - 2021 - Esterification of residual palm oil using solid ac DOI: 10.1016/j.jtice.2012.07.001.
• 1130 cm⁻¹ confidence 1.0

  “The bands around 1130 and 1150cm(cid:1)1 are due to the symmetric SO stretching and SO 2”

  Synergistic effect of copolymers composition on the electrochemical, thermal, and electrical behavior of 5-lithiosulphoisophthalic acid doped poly(aniline-co-2-isopropylaniline): synthesis, characterization, and applications DOI: 10.1002/pat.1359
• 1163 cm⁻¹ confidence 1.0

  “The peak at 1163 cm-1 in the CNC spectrum revealed the presence of a sulphated group (SO2) cm-1”

  Isolation and Characterization of Cellulose Nanocrystals from Oil Palm Mesocarp Fiber DOI: 10.3390/polym9080355
• 1318 cm⁻¹ confidence 1.0

  “(cm(cid:3)1) Band Vibration mode Main attribution Raw material Standard b-D-glucan M26/08 M49/07 M23/08 C@O 1647 v Conjugated carbonyl 1648 1655 1655 1646 CAH das 1445 CH3, CH2 1431 1436 1431 1420 CAH ds 1379 CH3 1374 1375 1375 1377 SAO 135”

  Choong 等 - 2014 - Identification of geographical origin of Lignosus DOI: 10.1016/j.molstruc.2014.04.001
• 1168 cm⁻¹ confidence 1.0

  “In the heparin-modified sample, there are peaks around 1168 cm-1 and 1240 cm-1, which correspond to the S-O and S=O bands.”

  Surface Heparinization of a Magnesium-Based Alloy: A Comparison Study of Aminopropyltriethoxysilane (APTES) and Polyamidoamine (PAMAM) Dendrimers DOI: 10.3390/jfb13040296
• 1651 cm⁻¹ confidence 1.0

  “Meanwhile, the presence of the peak at the 1651 cm-1, were assigned asymmetric O=S=O sulfonic group in SPEEK was confirmed by the sharp peak at 1024.13 cm-1, which were stretching vibration.”

  Hasbullah 等 - 2016 - Synthesis and Characterizations of Electrospun Sul DOI: 10.1063/1.4948867
• 1250 cm⁻¹ confidence 1.0

  “LLM confirmed rule peak-group candidate”

  Sulfated polysaccharides (fucoidan) from the brown seaweed Silvetia compressa (J. Agardh) E. Serrão, T.O. Cho, S.M. Boo & Brawley DOI: 10.1007/s10811-019-01870-1