What absorbs at 2138 cm⁻¹ in an FTIR spectrum?
A band near 2138 cm⁻¹ can point to several functional groups. Below are the most likely assignments, ranked by how much published evidence supports each — every one traceable to literature (DOI) and cross-validated against our 130,000+ reference spectra and knowledge graph.
Backed by 6 cited sources
クイックアンサー
A band near 2138 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.
可能性のある官能基アサイン
| 官能基 | 裏付け事実 | 引用元 | 最高信頼度 |
|---|---|---|---|
| Carbonyl (C=O) | 3 | 3 | 1.0 |
| Carboxyl (COOH) | 2 | 2 | 1.0 |
| Alkyl C-H | 1 | 1 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Ester | 1 | 1 | 1.0 |
| Amide | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
| C#c | 1 | 1 | 0.9 |
| Adsorbed carbon monoxide | 1 | 0 | 1.0 |
ランキングは蓄積された文献証拠を反映しており、単一の権威あるルールではありません。常にサンプルのコンテキストと照合して確認してください。
スペクトルロジック
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 2138 cm⁻¹ is usually not enough for material identification by itself.
実使用例
この種のクエリは、ポリマー識別、未知のプラスチックスクリーニング、QCトラブルシューティング、リサイクル材料の検証、および文献に基づいたピーク帰属のレビューで一般的です。
よくある間違い
- 少なくとも1～2つの支持ピークを確認せずに、1つの孤立したバンドを材料の証拠として扱うこと。
- 重複を無視: 複数の官能基が同じ波数付近に寄与することがあります。
- 添加剤、ブレンド、酸化、または汚染がスペクトルを歪める可能性がある場合に検証を省略すること。
検証アドバイス
曖昧さが残る場合は、特にブレンド、劣化サンプル、充填ポリマーについて、DSC、GC-MS、またはTGAで仮説を検証してください。
これらのアサインの根拠となる文献
-
Carbonyl (C=O) 信頼度 1.0
“With time, the bands at 2138, most stable carbonyl band and the bands in the 1774cm(cid:2)1 2249cm(cid:2)1 region are evidently due to carbonyls on reduced chromium spedevelop, the band at de1902, 1794 and”
Influence of dealumination and treatments on the chromium speciation in zeolite CrBEA DOI: 10.1016/j.micromeso.2009.04.038 -
Carbonyl (C=O) 信頼度 1.0
“groups34,53-55 to evacuation, characteristic of CH and CH that as corroborated by the observation of their characteristic di3 2 cm-1 evidence the formation of acyclic hydrocarbon species (Figure carbonyl bands at 2138 and 2095 at low CO cov”
Moussa 等 - 2018 - Nature of Active Nickel Sites and Initiation Mecha DOI: 10.1021/acscatal.7b03970 -
Acetate 信頼度 1.0
“C=O stretch 2138 2343 1722 1700 1590 bend 1494 C-H sym.”
Raunier 等 - 2004 - Tentative identification of urea and formamide in DOI: 10.1051/0004-6361:20034558 -
Carboxyl (COOH) 信頼度 1.0
“OH asymmetrical stretching 2360.30 OH asymmetrical stretching vibration in carboxylic acids vibration in carboxylic acids 2138 -”
Biocatalytic activity of Aspergillus niger xylanase in paper pulp biobleaching DOI: 10.1007/s13205-016-0480-0 -
C#c 信頼度 0.9
“Explicit assignment: 2371.88, 2345.87 and 2138.23 (C≡C)”
Pinto Cotrim 等 - 2016 - Preparation of beta-CyclodextrinLatex Dispersion DOI: 10.7569/JRM.2015.634122 -
信頼度 0.8
“Text: 'The band at 2138 cm-1 quickly disappear' in context of CO.”
Spezzati 等 - 2017 - Atomically Dispersed Pd-O Species on Ceo(2)(111) a DOI: 10.1021/acscatal.7b02001
このバンドを持つスペクトルがありますか？
FTIRスペクトルをアップロードすると、数秒で完全な解釈レポート（文献引用付きピークアサイン、ライブラリマッチ、信頼度評価付き証拠チェーン）を取得できます。