What absorbs at 1691 cm⁻¹ in an FTIR spectrum?

빠른 답변

A band near 1691 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.

가능한 작용기 할당

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스펙트럼 로직

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 1691 cm⁻¹ is usually not enough for material identification by itself.

실제 사용

이러한 유형의 질의는 고분자 식별, 미지 플라스틱 스크리닝, QC 문제 해결, 재활용 재료 검증 및 문헌 기반 피크 할당 검토에서 일반적입니다.

일반적인 실수

• 하나의 고립된 밴드를 재료의 증거로 취급하고 최소 하나 또는 두 개의 지원 피크를 확인하지 않는 것.
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검증 조언

모호성이 남아 있는 경우, 특히 혼합물, 분해된 시료 및 충전 폴리머의 경우 DSC, GC-MS 또는 TGA로 가설을 검증하십시오.

이 할당의 배경이 되는 문헌

• Water (H2O) 신뢰도 1.0

  “This side chain is increased, allowing water molecules to fully solvate the D-ringcarbonylandshiftingthevibrationalfrequencyto1691cm-1.”

  Chenchiliyan 等 - 2023 - Ground-state heterogeneity and vibrational energy DOI: 10.1063/5.0135268
• Protein 신뢰도 1.0

  “(1656cm(cid:2)1), a-helix b-sheet and Krimm [20] observed that The thyroid spectra, in addition to evident strong protein peaks 1691cm(cid:2)1) (1647cm(cid:2)1) (1626, 1679, and unordered secondary cm(cid:2)1 1659cm(cid:2)1, at 1547 and als”

  Das 等 - 2008 - FTIR of touch imprint cytology A novel tissue dia DOI: 10.1016/j.jphotobiol.2008.05.012
• Protein 신뢰도 1.0

  “Another peak at 1691 was likely (cid:2)-sheet indicative of a structure formed by unfolding and aggreof the protein via lyophilization [44].”

  Additives affecting thermal stability of salmon calcitonin in aqueous solution and structural similarity in lyophilized solid form DOI: 10.1016/j.procbio.2011.08.017
• C=n 신뢰도 1.0

  “The C=N stretching frequency of free aminoguanidine cm-1, bicarbonate is known to occur at 1691 and a peak was observed in the complexes at cm-1, 1650 indicating that the imine nitrogen atom is involved in the complexation.”

  Synthesis and Crystal Structure of [Ni(Amgu)2]X2 – Novel Solid-State Precursors for NiO Nanoparticles DOI: 10.1016/j.ica.2018.07.021
• C c single bond 신뢰도 1.0

  “weak C-H stretching at 3.86.05 3810.57 3859.98 We further observed sharp asymmetric C = O cm-1, cm-1 carboxylate at 1691.28 C-C ring stretching at 1419.30 and C-N stretching of a tertiary amine at cm-1.”

  Characterizing and demonstrating the role of Klebsiella SSN1 exopolysaccharide in osmotic stress tolerance using neutron radiography DOI: 10.1038/s41598-023-37133-w
• Acetate 신뢰도 1.0

  “cm-1 The narrow peak at 1691 fits chiefly to C=O stretching.”

  Influence of gamma irradiation on rosin properties and its antimicrobial activity DOI: 10.1038/s41598-023-31372-7
• Acetate 신뢰도 1.0

  “Based on the study of the FTIR spectrum of cm-1, the FTIR spectrum of DMPA, the C=O absorption peak of DMPA is located at 1691 which DMPA, the C=O absorption peak of DMPA is located at 1691 cm-1, which proves that the prepolymers”

  Synthesis of Linseed Oil-Based Waterborne Urethane Oil Wood Coatings DOI: 10.3390/polym10111235
• Amide 신뢰도 1.0

  “1940.31 - 1999.62,1951.55 1905.70 Allene Results concerning the banana peels derived activated carbon were stretching) similar to those reported by Zheng and Wang [34], whereas some peaks - 1690.75 - - Primary amide (C--O stretching) were i”

  Preparation and characterization of activated carbon from agricultural wastes and their ability to remove chlorpyrifos from water DOI: 10.1016/j.toxrep.2023.01.011