What absorbs at 739 cm⁻¹ in an FTIR spectrum?
A band near 739 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 5 cited sources
Jawapan pantas
A band near 739 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 |
|---|---|---|---|
| Alkyl C-H | 3 | 3 | 1.0 |
| Aromatic ring | 2 | 2 | 1.0 |
| Alkene (C=C) | 1 | 1 | 1.0 |
| Ring structure | 1 | 1 | 1.0 |
| C c single bond | 1 | 1 | 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 |
|---|---|---|---|
| chitosan | 739, 1650, 1655 | Alkyl C-H | 1 |
| GO | 739, 1720, 1182 | Alkyl C-H | 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 739 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
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Alkyl C-H keyakinan 1.0
“Meanwhile, numerous strong bands 739 804 cm-1, cm-1, cm-1 863 898 and 1455 in DiaRoot suggested the stretching of C-H groups.”
Assiry 等 - 2023 - Microstructural and Elemental Characterization of DOI: 10.3390/app13074517 -
C c single bond keyakinan 1.0
“Meanwhile, the peak at assigned 781, 767, 772, 735, 739 cm-1 corresponded to the C-C stretching vibration of the benzene ring [19].”
Modification of Hydroxypropyltrimethyl Ammonium Chitosan with Organic Acid: Synthesis, Characterization, and Antioxidant Activity DOI: 10.3390/polym12112460 -
Alkyl C-H keyakinan 1.0
“As a result of this experiment, we has peaks at 739 769 and cm-1 differently observed colored areas in the reaction tube with 815 assigned to out-of-plane CH bending vibrations orange products accumulated in the region of higher tempertypic”
Talyzin 等 - 2014 - Hydrogen-Driven Cage Unzipping of C-60 into Nano-G DOI: 10.1021/jp500377s -
Aromatic ring keyakinan 1.0
“Besides, the peaks at 1560 and 739 corresponded to stretching vibration of aromatic C=C to the successful modification that the molecular chain of HNH was grafted onto the surface of rGO.”
One-Step Reduction and Surface Modification of Graphene Oxide by 3-Hydroxy-2-Naphthoic Acid Hydrazide and Its Polypropylene Nanocomposites DOI: 10.3390/nano7020025 -
keyakinan 0.8
“Same as above.”
Purification and Glutaraldehyde Activation Study on HCl-Doped PVA–PANI Copolymers with Different Aniline Concentrations DOI: 10.3390/molecules24010063
Ada spektrum dengan jalur ini?
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