What absorbs at 730 cm⁻¹ in an FTIR spectrum?
A band near 730 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
Quick answer
A band near 730 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.
Possibili assegnazioni di gruppi funzionali
| Gruppo funzionale | Fatti di supporto | Fonti citate | Affidabilità massima |
|---|---|---|---|
| Alkyl C-H | 9 | 7 | 1,0 |
| Phosphate (PO4) | 5 | 3 | 1,0 |
| Metal oxygen | 4 | 4 | 1,0 |
| Silicon-oxygen (Si-O) | 4 | 4 | 1,0 |
| Siloxane (Si-O-Si) | 3 | 3 | 1,0 |
| Silicon (Si) | 3 | 3 | 1,0 |
| Aromatic ring | 2 | 2 | 1,0 |
| Carbonyl (C=O) | 2 | 1 | 1,0 |
| C c single bond | 1 | 1 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
| C-S single bond | 1 | 1 | 1,0 |
| Borate | 1 | 1 | 1,0 |
| Anhydride | 1 | 1 | 1,0 |
| Imide | 1 | 1 | 1,0 |
| Lipid | 1 | 1 | 1,0 |
| Perchlorate | 1 | 1 | 1,0 |
| Alkene (C=C) | 1 | 0 | 1,0 |
| Methacrylate | 1 | 0 | 1,0 |
| Ketone | 1 | 0 | 1,0 |
| Ester | 1 | 0 | 1,0 |
| Carboxyl (COOH) | 1 | 0 | 1,0 |
| Amide | 1 | 0 | 1,0 |
| Acetate | 1 | 0 | 1,0 |
La classifica riflette le prove bibliografiche accumulate, non una singola regola autorevole. Conferma sempre nel contesto del tuo campione.
Possible materials
| Materiale | Picchi di supporto | Overlapping groups | Fonti citate |
|---|---|---|---|
| asphalt binder | 730, 1700, 1242 | Alkyl C-H | 1 |
Materials are shown only when the same literature pool supports this band and at least one additional characteristic peak.
Spectrum logic
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 730 cm⁻¹ is usually not enough for material identification by itself.
Real-world usage
This type of query is common in polymer identification, unknown plastic screening, QC troubleshooting, recycled-material verification, and literature-backed peak assignment review.
Common mistakes
- Treating one isolated band as proof of a material without checking at least one or two supporting peaks.
- Ignoring overlap: multiple functional groups can contribute near the same wavenumber.
- Skipping validation when additives, blends, oxidation, or contamination may distort the spectrum.
Verification advice
When ambiguity remains, validate the hypothesis with DSC, GC-MS, or TGA, especially for blends, degraded samples, and filled polymers.
Letteratura dietro queste assegnazioni
-
Alkyl C-H affidabilità 1,0
“and Py with initial mass ratio (i.e., 14, 24, 32, and 40 wt%) The C-H out of plane bending vibration band was observed was added into the solution and mixture was stirred at room at 730 cm-1 for PNPhPy [27].”
Cetiner 等 - 2011 - Characterization of Conductive Poly(Acrylonitrile- DOI: 10.1007/s12221-011-0151-z -
Perchlorate affidabilità 1,0
“The 4) and EC solution, considerable a lithium perchlorate (LiClO cm-1 gel exhibits predominantly ionic nature and a 0.67 of appear corresponding to the shoulders at 730 and 900 cm-1 lithium ion transference number.”
Electrical and structural studies of a LiBOB-based gel polymer electrolyte DOI: 10.1007/s11581-016-1834-7 -
affidabilità 1,0
“699cm-1, centhydrocarbonchainsandthesplitismorepronouncedatlower the Due to the strong peak of Si-O-Al bending at 730cm-1 temperature with an orthorhombic subcell [28].”
Li 等 - 2008 - An FTIR investigation of hexadecyltrimethylammoniu DOI: 10.1016/j.saa.2008.05.015 -
Lipid affidabilità 1,0
“Asphalt binders cm-1, modified with wax-type additives showed peak response at 730 and 1540 which represents a double stretching bond of carbon and a single stretching bond between nitrogen and oxygen.”
Analysis of the Properties of Modified Asphalt Binder by FTIR Method DOI: 10.3390/ma15165743 -
Carbonyl (C=O) affidabilità 1,0
“The absorption bands at 730 and cm-1 1780 are attributed to carbonyl groups in both imide and anhydride rings.”
Yang 等 - 2016 - Comparison of different methods for determining th DOI: 10.1007/s10118-016-1749-9. -
affidabilità 1,0
“The band at 730 is attributed to the Zn-O The calculated mesh parameters of the powders are equal to a group, while the two bands, respectively, at 3014.24 and cm-1, = 17.92690 Å, b = 19.26990 Å, and c = 50.45000 Å.”
Adala 等 - 2022 - Two Coordination Polymers Synthesized from Various DOI: 10.1021/acsomega.1c06049 -
Borate affidabilità 1,0
“The vibrational modes at 1450, 1315, and peak at of the B 3 730cm-1 B-Cl B-O exposure.48 There may also be vibrations are attributed to vibrations as discussed earlier surface after BCl 3 1500cm-1”
Spontaneous etching of B2O3 by HF gas studied using infrared spectroscopy, mass spectrometry, and density functional theory DOI: 10.1116/6.0001542 -
C-S single bond affidabilità 1,0
“C=O stretching 1724 O-H Overlapping (def.) of C=C ring stretching 1585, 1442 C-O stretching due to phenol 1263 C-H C=C-H (def.) of (o.o.p.) from aromatic rings 800 Weak absorption indicating C-S stretching 730, 710, 678 reported melanins ar”
Purification and characterisation of a sulphur rich melanin from edible mushroom Termitomyces albuminosus Heim DOI: 10.1080/21501203.2018.1494060
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