What absorbs at 1205 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 1205 cm⁻¹ is usually interpreted by checking which functional groups repeatedly co-occur there in the literature, then confirming at least one or two additional peaks in the same sample. This page ranks those assignments by accumulated evidence rather than by a single fixed textbook rule.

가능한 작용기 할당

순위는 단일 권위 규칙이 아닌 축적된 문헌 증거를 반영합니다. 항상 샘플 상황에 대해 확인하세요.

Possible materials

Materials are shown only when the same literature pool supports this band and at least one additional characteristic peak.

Spectrum logic

This band becomes meaningful only when read with its neighboring peaks. In practice, analysts first look at the assignments above, then check whether the same sample also shows other peaks expected for the same structural motif. A lone band near 1205 cm⁻¹ is usually not enough for material identification by itself.

Real-world usage

This type of query is common in polymer identification, unknown plastic screening, QC troubleshooting, recycled-material verification, and literature-backed peak assignment review.

Common mistakes

• Treating one isolated band as proof of a material without checking at least one or two supporting peaks.
• Ignoring overlap: multiple functional groups can contribute near the same wavenumber.
• Skipping validation when additives, blends, oxidation, or contamination may distort the spectrum.

Verification advice

When ambiguity remains, validate the hypothesis with DSC, GC-MS, or TGA, especially for blends, degraded samples, and filled polymers.

이 할당의 배경이 되는 문헌

• Acetate 신뢰도 1.0

  “C=O stretching vibration C-F 1205, 1148 1303, 1149 C-F stretching vibration Si-O-C”

  Ganie 等 - 2020 - Synthesis and Characterization of a New Surface-Mo DOI: 10.1155/2020/8814260
• Aromatic ring 신뢰도 1.0

  “santalinus only at 1594 cm-1, 1205 cm-1, 1155 cm-1 and 836 cm-1, corresponding to the stretching vibration of carbon atoms in the aromatic framework, C-O-C stretching vibration in extractives, C-O-”

  Jin 等 - 2022 - Rapid Identification for the Pterocarpus Bracelet DOI: 10.3390/molecules27154793
• Carboxyl (COOH) 신뢰도 1.0

  “2 2 cm-1 When D 2O was used instead of water, the shifting of D 2O band bending at 1205 revealed (COO-) the same vibrational bands that corresponded to the symmetric and antisymmetric ν stretching vibrations (Fig.”

  Belhadj 等 - 2016 - Pathways of the photocatalytic reaction of acetate DOI: 10.1016/j.jcat.2016.08.006
• S eq o 신뢰도 1.0

  “Presence of sulfate groups on NCC, not present on 404 cm-1, original fibers is illustrated by a small peak at 1205 which can be attributed to S=O 405”

  Beltramino 等 - 2016 - Optimization of sulfuric acid hydrolysis condition DOI: 10.1007/s10570-016-0897-y
• 신뢰도 1.0

  “Samples Li0.4, Li0.6, Li0.8, Na0.33, and Na0.5 have similar (see Section 3.3.3), and are dominated by the strong Si-O stretching envelope at ~1000 cm-1 (the weak spectra with complex Si-O profiles which are biased by optical dispersion effe”

  The Nature of Laponite: Pure Hectorite or a Mixture of Different Trioctahedral Phases? DOI: 10.3390/min8080314
• Alkyl C-H 신뢰도 1.0

  “The FTIR-ATR spectrum from Figure 2b shows the characteristic vibration of C-fibers at 1451, The FTIR-ATR spectrum from Figure 2b shows the characteristic vibration of C-fibers at 1451, The FTIR-ATR spectrum from Figure 2b shows the charact”

  Drobota 等 - 2020 - Preparation and Characterization of Electrospun Co DOI: 10.3390/ma13183961
• Silicon (Si) 신뢰도 1.0

  “The weaker bands at 1137 1205cm-1 O bonds (E symmetry) lead to the intense band centred at and are assigned to Si-O stretching in the eight- ∼975cm-1 in Lz.”

  Fritsch 等 - 2021 - Structural, textural, and chemical controls on the DOI: 10.5194/ejm-33-447-2021
• Metal oxygen 신뢰도 1.0

  “at 1050 and 1260 on spectrum 5b demonstrates that no In order to eliminate spectral features due to changes in the changes in the oxide layer occurred during the reaction with F(CH thin surface oxide layer during the reaction with CH 3OH, t”

  Michalak 等 - 2008 - Investigation of the chemical purity of silicon su DOI: 10.1021/jp8030539