What absorbs at 1187 cm⁻¹ in an FTIR spectrum?
A band near 1187 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 8 cited sources
Răspuns rapid
A band near 1187 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.
Atribuiri posibile ale grupelor funcționale
| Grup funcțional | Fapte suport | Surse citate | Încredere maximă |
|---|---|---|---|
| Methacrylate | 6 | 6 | 1,0 |
| Acetate | 6 | 6 | 1,0 |
| Methoxy (OCH3) | 5 | 5 | 1,0 |
| C-O single bond | 5 | 5 | 1,0 |
| Secondary amine | 3 | 3 | 1,0 |
| Amide | 3 | 3 | 1,0 |
| C n single bond | 2 | 2 | 1,0 |
| N h | 2 | 2 | 1,0 |
| Ester | 2 | 2 | 1,0 |
| Amine primary | 1 | 1 | 1,0 |
| Silicon-oxygen (Si-O) | 1 | 1 | 1,0 |
| Silicon (Si) | 1 | 1 | 1,0 |
| Siloxane (Si-O-Si) | 1 | 1 | 1,0 |
| Alkyl C-H | 1 | 1 | 1,0 |
| Alkene (C=C) | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Carbonyl (C=O) | 1 | 1 | 1,0 |
Clasamentul reflectă dovezile acumulate din literatură, nu o singură regulă autoritară. Confirmați întotdeauna în contextul mostrei dvs.
Materiale posibile
| Material | Vârfuri suport | Grupuri suprapuse | Surse citate |
|---|---|---|---|
| Nanocellulose | 1187, 1540, 1646 | Methacrylate, Acetate, C-O single bond | 1 |
Materialele sunt afișate numai atunci când același grup de literatură susține această bandă și cel puțin un vârf caracteristic suplimentar.
Logica spectrului
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 1187 cm⁻¹ is usually not enough for material identification by itself.
Utilizare în condiții reale
Acest tip de interogare este comun în identificarea polimerilor, screeningul materialelor plastice necunoscute, depanarea QC, verificarea materialelor reciclate și revizuirea atribuirii vârfurilor bazată pe literatură.
Greșeli comune
- Tratarea unei benzi izolate ca dovadă a unui material fără a verifica cel puțin unul sau două vârfuri de susținere.
- Ignorând suprapunerea: mai multe grupuri funcționale pot contribui în apropierea aceluiași număr de undă.
- Omiterea validării atunci când aditivii, amestecurile, oxidarea sau contaminarea pot distorsiona spectrul.
Sfat de verificare
Când ambiguitatea rămâne, validați ipoteza prin DSC, GC-MS sau TGA, în special pentru amestecuri, probe degradate și polimeri umpluți.
Literatura din spatele acestor atribuiri
-
N h încredere 1,0
“that can be assigned to the NH Their observation of the absence of proton of E showed a band at 1187 bending vibration of a strongly hydrogen-bonded His and a release in the presence of o-phenanthroline, concomitant with cm-1 cm-1 band at 1”
Kimura 等 - 2020 - Protonation State of a Key Histidine Ligand in the DOI: 10.1021/acs.biochem.0c00810 -
Acetate încredere 1,0
“cm-1, cm-1), 2662 which characterize cyclic dimer, in-plane COH (1400 the CO bending vibrations cm-1) cm-1, (1714 and feature at 1700 which also characterizes the cyclic dimer, the COH bending cm-1 cm-1), (1400) and C-O stretching vibration”
Kondratenko 等 - 2020 - Thioglycolic Acid FTIR Spectra on Ag2S Quantum Dot DOI: 10.3390/ma13040909 -
Ester încredere 1,0
“cm-1 (1) EPMC due to the absorption at 1707 of the In this step, two amine compounds were used, namely cm-1 carbonyl ester strengthened by the band at 1186.86 phenethylamine and morpholine, to produce N-”
Rasyid 等 - 2022 - Synthesis of N-phenethyl-p-methoxycinnamamide and DOI: 10.22146/ijc.76802 -
Ester încredere 1,0
“and bands located between 1187 and 1277/cm that represented ester C=O vibrations.”
Biodegradation of P(3HB-co-4HB) powder by Pseudomonas mendocina for preparation low-molecular-mass P(3HB-co-4HB) DOI: 10.1007/s13205-017-0824-4 -
Acetate încredere 1,0
“The peaks at 1187 and 980 are 2 3 respectively attributed to the asymmetric stretching of C-O-C and the deformation of C=CH [43,44],”
Hosseini 等 - 2017 - Polymethacrylate Coated Electrospun PHB Fibers as DOI: 10.3390/s17102292 -
Amide încredere 1,0
“The -C-N band at wavenumbers 1187 and”
Preparation and Characterization of Indomethacin Supramolecular Systems with -Cyclodextrin in Order to Estimate Photostability Improvement DOI: 10.3390/molecules26247436 -
Siloxane (Si-O-Si) încredere 1,0
“Moreover, in the case of silane- -1 cm-1 samples, a peak at 1187 occurred and was attributed to the presence of siloxane”
APTES-Modified Nanocellulose as the Formaldehyde Scavenger for UF Adhesive-Bonded Particleboard and Strawboard DOI: 10.3390/polym14225037 -
Acetate încredere 1,0
“C-N, C-C and C-O stretching 1187 a 1015 A menu plot molecular graph, the electrostatic”
Rangel-Vazquez 等 - 2014 - Spectroscopy Analyses of PolyurethanePolyaniline DOI: 10.1590/0104-1428.1496
Aveți un spectru cu această bandă?
Încărcați spectrul FTIR și obțineți un raport complet de interpretare — atribuiri de peak-uri cu citări din literatură, potriviri cu biblioteca și un lanț de dovezi cu nivel de încredere — în câteva secunde.