What absorbs at 1840 cm⁻¹ in an FTIR spectrum?
A band near 1840 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
Ateb cyflym
A band near 1840 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.
Aseiniadau grŵp swyddogaethol posibl
| Grŵp swyddogaethol | Ffeithiau ategol | Ffynonellau a ddyfynnwyd | Hyder uchaf |
|---|---|---|---|
| Ester | 2 | 2 | 1.0 |
| Methoxy (OCH3) | 1 | 1 | 1.0 |
| C-O single bond | 1 | 1 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Carboxyl (COOH) | 1 | 1 | 1.0 |
| Carbonyl (C=O) | 1 | 1 | 1.0 |
| Amide | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
Mae'r safle'n adlewyrchu tystiolaeth llenyddiaeth gronnwyd, nid rheol awdurdodol sengl. Cadarnhewch bob amser yn erbyn eich cyd-destun sampl.
Deunyddiau posibl
| Deunydd | Copaon ategol | Grwpiau sy'n gorgyffwrdd | Ffynonellau a ddyfynnwyd |
|---|---|---|---|
| Polyester | 1840, 1700, 1250 | Methacrylate, Ester, Methoxy (OCH3) | 1 |
| glycerol | 1840, 1585, 1630 | Methacrylate, C-O single bond, Methoxy (OCH3) | 1 |
Mae deunyddiau'n cael eu dangos dim ond pan fydd yr un gronfa lenyddiaeth yn cefnogi'r band hwn ac o leiaf un brig nodweddiadol ychwanegol.
Rhesymeg sbectrwm
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 1840 cm⁻¹ is usually not enough for material identification by itself.
Defnydd yn y byd go iawn
Mae'r math hwn o ymholiad yn gyffredin mewn adnabod polymer, sgrinio plastig anhysbys, datrys problemau QC, dilysu deunydd wedi'i ailgylchu, ac adolygiad o aseiniad copa wedi'i gefnogi gan lenyddiaeth.
Camgymeriadau cyffredin
- Trin un band ynysig fel prawf o ddeunydd heb wirio o leiaf un neu ddau gopa cefnogol.
- Anwybyddu gorgyffwrdd: gall grwpiau swyddogaethol lluosog gyfrannu ger yr un rhif ton.
- Hepgor dilysu pan fo ychwanegion, cymysgeddau, ocsideiddio, neu halogiad yn gallu ystumio'r sbectrwm.
Cyngor dilysu
Pan fo amwysedd yn parhau, dilyswch y rhagdybiaeth gyda DSC, GC-MS, neu TGA, yn enwedig ar gyfer cymysgeddau, samplau dirywiedig, a pholymerau llawn.
Llenyddiaeth y tu ôl i'r aseiniadau hyn
-
Acetate hyder 1.0
“In the next step, citraconic anhydride was observable by the band at 1840 cm-1 and 1765 cm-1 (C=O stretching of anhydride compounds) and 920 cm-1 (C-O stretching of the C-O-C) [43,44].”
Bio-Based Phosphate-Containing Polyester for Improvement of Fire Reaction in Wooden Particleboard DOI: 10.3390/polym15051093 -
Ester hyder 1.0
“LLM confirmed rule peak-group candidate”
Yang 等 - 2015 - Improved Dissolution Behavior of Aceclofenac Loadi DOI: 10.7317/pk.2015.39.1.6 -
hyder 0.95
“Explicit assignment: 'bridge-bonded CO (CO B) species, which give rise to IR absorption near 1840 cm~1'”
Sun 和 Zhou - 2001 - Surface processes and kinetics of CO2 reduction on DOI: 10.1039/b100938i -
hyder 0.9
“Band in region of coordinated NO”
de Souza Gois 等 - 2019 - A ruthenium nitrosyl cyclam complex with appended DOI: 10.1016/j.poly.2019.114117 -
hyder 0.7
“Text: 'peaks at 1840 after ... multivacancy defects and hydrogen-terminated GeH were identified.'”
Rochat 等 - 2010 - Germanium and Silicon A Comparative Study of Hydr DOI: 10.1149/1.3329611(cid:4)
Oes gennych sbectrwm gyda'r band hwn?
Llwythwch eich sbectrwm FTIR i fyny a chael adroddiad dehongli llawn — aseiniadau brig gyda chyfeiriadau llenyddiaeth, cyfateb llyfrgell, a chadwyn dystiolaeth â gradd hyder — mewn eiliadau.