What absorbs at 1684 cm⁻¹ in an FTIR spectrum?
A band near 1684 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
Jawapan pantas
A band near 1684 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.
Penetapan kumpulan berfungsi yang mungkin
| Kumpulan berfungsi | Fakta sokongan | Sumber dipetik | Keyakinan tertinggi |
|---|---|---|---|
| Amide | 4 | 4 | 1.0 |
| Carbonyl (C=O) | 3 | 3 | 1.0 |
| Alkyl C-H | 3 | 3 | 1.0 |
| Aromatic ring | 3 | 3 | 1.0 |
| Carboxyl (COOH) | 3 | 3 | 1.0 |
| Ester | 2 | 2 | 1.0 |
| Methyl | 2 | 2 | 1.0 |
| Methacrylate | 2 | 2 | 1.0 |
| Acetate | 2 | 2 | 1.0 |
| Lipid | 1 | 1 | 1.0 |
| Methoxy (OCH3) | 1 | 1 | 1.0 |
| Fatty acid | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Hydrogen bond | 1 | 1 | 1.0 |
| Water (H2O) | 1 | 1 | 1.0 |
| Hydroxyl (O-H) | 1 | 1 | 1.0 |
| Alkene (C=C) | 1 | 0 | 1.0 |
Pemeringkatan mencerminkan bukti literatur terkumpul, bukan satu peraturan berwibawa. Sentiasa sahkan terhadap konteks sampel anda.
Bahan yang mungkin
| Bahan | Puncak sokongan | Kumpulan bertindih | Sumber dipetik |
|---|---|---|---|
| Methacrylate | 1684, 873, 1725 | Alkyl C-H, Carbonyl (C=O) | 1 |
| polyurethanes | 1684, 1740, 1728 | Amide, Carbonyl (C=O), Alkyl C-H | 1 |
| lignin | 1684, 1035, 1510 | Alkyl C-H, Aromatic ring | 1 |
Bahan hanya dipaparkan apabila kumpulan literatur yang sama menyokong jalur ini dan sekurang-kurangnya satu puncak ciri tambahan.
Logik spektrum
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 1684 cm⁻¹ is usually not enough for material identification by itself.
Penggunaan dunia sebenar
Jenis pertanyaan ini biasa dalam pengenalpastian polimer, saringan plastik tidak diketahui, penyelesaian masalah QC, pengesahan bahan kitar semula, dan semakan tugasan puncak yang disokong oleh literatur.
Kesilapan biasa
- Menganggap satu jalur terpencil sebagai bukti bahan tanpa memeriksa sekurang-kurangnya satu atau dua puncak sokongan.
- Mengabaikan pertindihan: pelbagai kumpulan berfungsi boleh menyumbang berhampiran nombor gelombang yang sama.
- Melangkau pengesahan apabila bahan tambahan, campuran, pengoksidaan, atau pencemaran boleh memesongkan spektrum.
Nasihat pengesahan
Apabila kekaburan masih ada, sahkan hipotesis dengan DSC, GC-MS, atau TGA, terutamanya untuk campuran, sampel terdegradasi, dan polimer terisi.
Literatur di sebalik penetapan ini
-
Hydroxyl (O-H) keyakinan 1.0
“J.-H.Liuetal./SpectrochimicaActaPartA61(2005)893-899 895 ∼1684cm-1 The O H stretching bands of pure water are generally for MgSO in the region of bending peak at”
Liu 等 - 2005 - Drawing out the structural information of the firs DOI: 10.1016/j.saa.2004.06.030 -
Carboxyl (COOH) keyakinan 1.0
“In addition, 1433.11 cm-1 Moreover, absorption of C=O obtained in 1683.86 4a the presence of the phenethyl group in was also indicated that the carbonyl group belongs to a carboxylic confirmed by the absorption band at 746.45 and acid moiet”
Rasyid 等 - 2022 - Synthesis of N-phenethyl-p-methoxycinnamamide and DOI: 10.22146/ijc.76802 -
Hydrogen bond keyakinan 1.0
“LLM confirmed rule peak-group candidate”
Time-dependent morphology development in segmented polyetherurea copolymers based on aromatic diisocyanates DOI: 10.1002/polb.21652 -
Carboxyl (COOH) keyakinan 1.0
“LLM confirmed rule peak-group candidate”
Transition Metal Oxodiperoxo Complex Modified Metal-Organic Frameworks as Catalysts for the Selective Oxidation of Cyclohexane DOI: 10.3390/ma13040829 -
Methyl keyakinan 1.0
“corresponding to aliphatic and aromatic -OH (3415 cm-1), aromatic ring modes (1595 cm-1 and 1140 cm-1), carbonyl group (1684 cm-1), aliphatic -CH3 (2944 cm-1) and CH2 groups (1453 cm-1), symmetric -CH3 stretching of the methoxyl groups (285”
Characterization and Evaluation of Hydrothermal Liquefaction Char from Alkali Lignin in Subcritical Temperatures DOI: 10.3390/ma14113024 -
Acetate keyakinan 1.0
“cm-1 The appearance of a C=O stretching vibration band at 1684 (as a "shoulder" cm-1 to the intrinsic 1673 band) in the spectra of all diltiazem-Eudragit RS 100 physical cm-1 The appearance of а C=O stretching vibration band at 1684 (as a "”
Kolev 等 - 2022 - Ammonio Methacrylate Copolymer (Type B)-Diltiazem DOI: 10.3390/polym14102125 -
Amide keyakinan 1.0
“We observed the primary amide III band band and amide I band were centered around ~1571 cm-1 and ~1684 cm-1, respectively, for tissues.”
Comprehensive Evaluation of PAXgene Fixation on Oral Cancer Tissues Using Routine Histology, Immunohistochemistry, and FTIR Microspectroscopy DOI: 10.3390/biom11060889 -
Alkyl C-H keyakinan 1.0
“f cm-1 cm-1 -C-H -C-H 2880.32 for aliphatic stretching, 1684.32 and FTIR: 3062.84 and 3028.98 for aromatic cm-1 cm-1 -N�CH-”
Manjare 等 - 2023 - Microwave-Assisted Rapid and Green Synthesis of Sc DOI: 10.1021/acsomega.2c05187
Ada spektrum dengan jalur ini?
Muat naik spektrum FTIR anda dan dapatkan laporan tafsiran penuh — penetapan puncak dengan petikan literatur, padanan perpustakaan, dan rantaian bukti berkadar keyakinan — dalam beberapa saat.