What absorbs at 2140 cm⁻¹ in an FTIR spectrum?

Быстрый ответ

A band near 2140 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.

Возможные назначения функциональных групп

Ранжирование отражает накопленные литературные данные, а не единственное авторитетное правило. Всегда проверяйте в контексте вашего образца.

Возможные материалы

Материалы отображаются только при поддержке данной полосы и хотя бы одного дополнительного характеристического пика из того же литературного пула.

Логика спектра

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 2140 cm⁻¹ is usually not enough for material identification by itself.

Использование в реальных условиях

Такой тип запроса распространен при идентификации полимеров, скрининге неизвестных пластиков, устранении неполадок в контроле качества, проверке переработанных материалов и анализе отнесения пиков на основе литературы.

Распространенные ошибки

• Рассмотрение одной изолированной полосы как доказательства материала без проверки хотя бы одного или двух поддерживающих пиков.
• Игнорирование перекрытия: несколько функциональных групп могут вносить вклад вблизи одного и того же волнового числа.
• Пропуск проверки, когда добавки, смеси, окисление или загрязнение могут исказить спектр.

Рекомендации по проверке

Когда остается неоднозначность, проверьте гипотезу с помощью DSC, GC-MS или TGA, особенно для смесей, деградированных образцов и наполненных полимеров.

Литература, лежащая в основе этих назначений

• Hydroxyl (O-H) достоверность 1,0

  “N-D identified that the stretching vibrations of the Schiff X-D most spectral changes in the stretching vibrations cm-1 (32) base in BR and ppR are located at 2171 and 2123 O-D N-D originate from either a water stretch or a stretch cm-1 and”

  Ota 等 - 2006 - Structural changes in the Schiff base region of sq DOI: 10.1021/bi051937l
• Hydroxyl (O-H) достоверность 1,0

  “Physisorbed CO results in a band at 2140 cm-1, whereas CO interacting with surface OH groups gives rise to a band at 2155 while cm-1 cm-1 another massif from 2180 to 2245 accounts for CO interacting with Lewis cm-1”

  Upgrading the PtCu intermetallic compounds: The role of Pt and Cu in the alloy DOI: 10.1016/j.cattod.2019.11.026
• Silicon hydride достоверность 1,0

  “Whereas the decrease in the CH bands intensities and the simultaneous 3 cm-1 increase of the Si-H absorption band intensity at 2140 at higher W/F values (hard plasma conditions), is due to the higher monomer fragmentation.”

  Comparative study of bulk and surface compositions of plasma polymerized organosilicon thin films DOI: 10.1002/ppap.201900024.
• Hydroxyl (O-H) достоверность 1,0

  “cm-1 and interaction with Here, the strong broadband centered at around 3291 and weak band at cm-1 around 2140 are ascribed to the inter molecular hydrogen bonded network formed by the hydroxyl groups”

  Bioinspired 5-caffeoylquinic acid capped silver nanoparticles using Coffee arabica leaf extract for high-sensitive cysteine detection DOI: 10.1038/s41598-023-34944-9
• достоверность 1,0

  “Based on our previous studies supported by DFT calculations [8,11], we assign the cm-1 2127 band to Pd(II)(OH)(CO) complex (or alternatively Pd(II)(CO) complex: we cannot cm-1 exclude either assignment at present) and the 2140 band to a dif”

  The superior hydrothermal stability of Pd/SSZ-39 in low temperature passive NOx adsorption (PNA) and methane combustion DOI: 10.1016/j.jcat.2010.07.031.
• C c single bond достоверность 1,0

  “LLM confirmed rule peak-group candidate”

  Microsoft Word - Rapid_synthesis_of_nanocrystalline_YAG_via_microwave_assisted_solvothermal_process_final_resubmit_jbBV (1) DOI: 10.1111/jace.15815
• Adsorbed carbon monoxide достоверность 1,0

  “cm-1, bands of carbon dioxide at 2317 and 3728 cm-1, the rotovibrational band due to CO deformation at bands of carbon dioxide at 2317 and 3728 the rotovibrational band due to CO deformation at 2 2 cm-1, cm-1), 771 the rotovibrational band”

  Thermocatalytic Pyrolysis of Exhausted Arthrospira platensis Biomass after Protein or Lipid Recovery DOI: 10.3390/en13205246
• C#c достоверность 1,0

  “Also, a small stretch at 2140 was found, which can be assigned to alkyne Apart cm-1 from this, a very sharp and intense peak was obtained at 1650 for C=O stretch representing α, β unsaturated cm-1 aldehydes and ketones.”

  Comparative assessment of green and chemically synthesized glutathione capped silver nanoparticles for antioxidant, mosquito larvicidal and eco-toxicological activities DOI: 10.1038/s41598-023-35249-7