What absorbs at 1425 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 1425 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.

Possible functional-group assignments

Ranking reflects accumulated literature evidence, not a single fixed rule. Always confirm against your sample context.

Possible materials

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 1425 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.

Literature behind these assignments

• Acetate confidence 1.0

  “1450and1400cm(cid:2)1(Guilianoetal.,2000).Thescissoringstrongpeakat cm(cid:2)1 was attributed to the cellulose I, while cellulose II and 1430 amorphous cellulose were characterized by weak peak detected at 1420 cm(cid:2)1(Songetal.,2015).On”

  Structural characterization of Argania spinosa Moroccan wooden artifacts during natural degradation progress using infrared spectroscopy (ATR-FTIR) and X-Ray diffraction (XRD) DOI: 10.1016/j.heliyon.2019.e02477
• Acetate confidence 1.0

  “1112 C-C, C-O stretching in holocellulose 1425 1426 Aromatic skeletal vibration in lignin and C-H deformation in-plane deforming 1058”

  Jin 等 - 2022 - Rapid Identification for the Pterocarpus Bracelet DOI: 10.3390/molecules27154793
• Alkyl C-H confidence 1.0

  “At the same cm1 time, in the region of 1425 related to bending vibrations of -CH 2groups, the signal intensity cm1 decreases, and the intensity of the absorption band at 1315 related to fan-shaped vibrations of - CH 2groups, which are assoc”

  Makhliyo 等 - 2023 - Preparation of oxidized nanocellulose by using pot DOI: 10.21203/rs.3.rs-2033622/v1
• Alkyl C-H confidence 1.0

  “Peak at 1425 attributed to vibration of CH group, 2 membrane were estimated using Rabek's method using following”

  Fabrication and characterization of modified microcrystalline cellulose membrane as proton exchange membrane for direct methanol fuel cell DOI: 10.1016/j.matpr.2021.01.431
• Carbohydrate confidence 1.0

  “We have calculated the ratios of the cm-1 cm-1 (1505 heights of lignin peaks at 1505/1511 against peaks at 1462 (for beech) and 1511 bands (for pine) cm-1 and 1425 against carbohydrate bands) although high weight losses (due to C-H, deforma”

  Pandey 和 Pitman - 2003 - FTIR studies of the changes in wood chemistry foll DOI: 10.1016/S0964-8305(03)00052-0
• Alkyl C-H confidence 1.0

  “More pronounced bands at 1425 (8), 1323 (10), 1105 (14), 1054 (15), and 897 (17) cm-1 which represent stretching vibration of -CH shear, C-H, C-O of secondary alcohol, C-C, and β2 glyosidic linkage in cellulose were clearly discernible, imp”

  Solihat 等 - 2020 - Microwave assisted dilute organic acid pre-treatme DOI: 10.1088/1757-899X/935/1/012046
• Carbonate confidence 1.0

  “a sharp peak at 1425 and attributed to carbonates and the decomposition of readily degradable organic matter, such (carbonates: C-O stretch vibration and C-O out of plane vibration, as aliphatic components, polysaccharides, and alcohols.”

  Evaluation of the biological stability of waste during landfill stabilization by thermogravimetric analysis and Fourier transform infrared spectroscopy DOI: 10.1016/j.biortech.2011.07.029
• confidence 1.0

  “stretching and aromatic skeletal vibration were important oxygen but is more likely to be an interaction band between 1425cm-1 carbon single bonded oxygen stretch and in-plane carbon , respectively loadings at 1735, 1658, 1328, 1510, and Jo”

  Zhou 等 - 2015 - Multivariate Calibration and Model Integrity for W DOI: 10.1155/2015/429846