What absorbs at 1277 cm⁻¹ in an FTIR spectrum?
A band near 1277 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
Rychlá odpověď
A band near 1277 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.
Možná přiřazení funkčních skupin
| Funkční skupina | Podpůrná fakta | Citované zdroje | Nejvyšší spolehlivost |
|---|---|---|---|
| Methacrylate | 6 | 6 | 1,0 |
| Acetate | 6 | 6 | 1,0 |
| Methoxy (OCH3) | 5 | 5 | 1,0 |
| C-O single bond | 5 | 5 | 1,0 |
| Amide | 5 | 5 | 1,0 |
| Secondary amine | 5 | 5 | 1,0 |
| C n single bond | 4 | 4 | 1,0 |
| Ester | 2 | 2 | 1,0 |
| Protein alpha helix | 1 | 1 | 1,0 |
| N h | 1 | 1 | 1,0 |
| Phosphate (PO4) | 1 | 1 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Carbonyl (C=O) | 1 | 1 | 1,0 |
| Aromatic ring | 1 | 1 | 1,0 |
| Ring structure | 1 | 1 | 1,0 |
| C c single bond | 1 | 1 | 1,0 |
| Alkyl C-H | 1 | 1 | 0,9 |
| Sulfonate | 1 | 0 | 1,0 |
| Bromine | 1 | 0 | 1,0 |
Pořadí odráží nahromaděné literární důkazy, nikoli jediné autoritativní pravidlo. Vždy potvrďte v kontextu vašeho vzorku.
Možné materiály
| Materiál | Podpůrné píky | Překrývající se skupiny | Citované zdroje |
|---|---|---|---|
| polyvinylpyrrolidone | 1277, 1660, 1700 | Methacrylate, Acetate | 1 |
| PVP | 1277, 2983, 1648 | Methacrylate, Acetate | 1 |
Materiály jsou zobrazeny pouze tehdy, když stejný literární soubor podporuje tento pás a alespoň jeden další charakteristický pík.
Logika spektra
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 1277 cm⁻¹ is usually not enough for material identification by itself.
Reálné použití
Tento typ dotazu je běžný při identifikaci polymerů, screeningu neznámých plastů, řešení problémů s QC, ověřování recyklovaných materiálů a kontrole přiřazení píků podložené literaturou.
Běžné chyby
- Považování jednoho izolovaného pásu za důkaz materiálu bez kontroly alespoň jednoho nebo dvou podpůrných píků.
- Ignorování překryvu: více funkčních skupin může přispívat poblíž stejného vlnočtu.
- Přeskakování validace, když mohou aditiva, směsi, oxidace nebo kontaminace zkreslit spektrum.
Rady pro ověření
Pokud přetrvává nejednoznačnost, ověřte hypotézu pomocí DSC, GC-MS nebo TGA, zejména u směsí, degradovaných vzorků a plněných polymerů.
Literatura za těmito přiřazeními
-
Amide spolehlivost 1,0
“NFs synthesized at 60 are cm-1 C-N band at 1277 can be assigned to the stretching found to be thinner and broader in size according to the”
Performance of Polyaniline Nanofibers (PANI NFs) as PANI NFs-Silver (Ag) Nanocomposites (NCs) for Energy Storage and Antibacterial Applications DOI: 10.1021/acsomega.8b02834 -
C c single bond spolehlivost 1,0
“., , -1 -1 cm (C-N stretch) and 1276.88 cm (C-C, C-H, O-H stretch).”
Maity 等 - 2017 - Polyhydroxyalkanoates production by Zobellella spe DOI: 10.22438/jeb/38/6/MRN-533 -
Acetate spolehlivost 1,0
“wagging at 1335 The peaks at 1277 and 1159 are ascribed cm(cid:0) 1 C-O-C An aliquot of the wine samples (6 mL) was passed through the carto the stretching of the ether bonds in cycles.”
Characterization of the medium infrared spectra of polyphenols of red and white wines by integrating FT IR and UV–Vis spectral data DOI: 10.1016/j.lwt.2021.111604 -
Amide spolehlivost 1,0
“1316 Strong C-N stretching Aromatic amine 1277 Strong”
Evaluation of anticandidal activities and phytochemical examination of extracts prepared from DOI: 10.1186/s12906-022-03552-x -
Amide spolehlivost 1,0
“The band cm-1 observed at 1277 is associated with C-N stretching, cm-1, and the two distinct bands occur at 838 and cm-1 639 related to the C-C ring and C-N=O bending,”
Alibe 等 - 2019 - Effects of polyvinylpyrrolidone on structural and DOI: 10.1007/s10973-018-7874-7 -
Aromatic ring spolehlivost 1,0
“The band at 1650 cm-1 has been assigned to the carbonyl stretching vibration, a number of skeletal ring vibrations at 1598, 1490 and 1413 cm-1, the asymmetric stretching of ether group at 1277 and 1190 cm-1, the aromatic hydrogen in-plane d”
Mechano-Chemical Properties of Electron Beam Irradiated Polyetheretherketone DOI: 10.3390/polym14153067 -
Acetate spolehlivost 1,0
“CP presented a characteristic peak at 2976 cm-1 cm-1 cm-1 2976 (C-H stretching vibration), the peak at 1622 was due to the C=O stretching (C-H stretching vibration), the peak at 1622 cm-1 was due to the C=O stretching and 1277 cm-1 cm-1 and”
Almotairi 等 - 2022 - Design and Optimization of Lornoxicam Dispersible DOI: 10.3390/ph15121463 -
Hydroxyl (O-H) spolehlivost 1,0
“The intense band at 1277 is attributed to (CO) asym vibration due to the deprotonated species derived from the hydroxyl group.”
Chavan 等 - 2013 - Fundamental Aspects of H2S Adsorption on CPO-27-Ni DOI: 10.1021/jp402440u
Máte spektrum s tímto pásem?
Nahrajte své FTIR spektrum a získejte plnou interpretační zprávu – přiřazení píků s citacemi literatury, shody s knihovnou a řetězec důkazů s hodnocením spolehlivosti – během několika sekund.