What absorbs at 645 cm⁻¹ in an FTIR spectrum?
A band near 645 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 3 cited sources
Quick answer
A band near 645 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.
সম্ভাব্য কার্যকরী-গ্রুপ অ্যাসাইনমেন্ট
| কার্যকরী গ্রুপ | সমর্থনকারী তথ্য | উদ্ধৃত সূত্র | সর্বোচ্চ আত্মবিশ্বাস |
|---|---|---|---|
| Secondary amine | 1 | 1 | 1.0 |
| N h | 1 | 1 | 1.0 |
| Metal oxygen | 1 | 1 | 1.0 |
| Bromine | 1 | 1 | 1.0 |
| Carbonate | 1 | 0 | 1.0 |
| C c single bond | 1 | 0 | 1.0 |
র্যাঙ্কিং জমা হওয়া সাহিত্য প্রমাণ প্রতিফলিত করে, একটি একক কর্তৃত্বপূর্ণ নিয়ম নয়। সর্বদা আপনার নমুনা প্রসঙ্গের বিরুদ্ধে নিশ্চিত করুন।
Possible materials
| উপাদান | সমর্থনকারী শিখর | Overlapping groups | উদ্ধৃত সূত্র |
|---|---|---|---|
| chitosan | 645, 1650, 1655 | N h | 1 |
| magnetite | 645, 1740, 1263 | Metal oxygen | 1 |
| iron oxide | 645, 1130, 891 | Metal oxygen | 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 645 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.
এই অ্যাসাইনমেন্টগুলোর পেছনে সাহিত্য
-
Bromine আত্মবিশ্বাস 1.0
“The cm(cid:0) Br-C 1 sensitive PLA-naringin coaxial electrospun fiber membrane, was stored absorption peaks at 645, 506, and 3500 were caused by the ◦C, Br-C”
Preparation of pH-sensitive polylactic acid-naringin coaxial electrospun fiber membranes for maintaining and monitoring salmon freshness DOI: 10.1016/j.ijbiomac.2021.08.087 -
আত্মবিশ্বাস 1.0
“In Figure 2, the FTIR spectra reveal the three characteristic peaks at 552 cm-1, 645 cm-1, and 990 cm-1 which are attributed to the Fe-O bond [50].”
Yadav 等 - 2020 - Synthesis and Characterization of Amorphous Iron O DOI: 10.3390/nano10081551 -
N h আত্মবিশ্বাস 1.0
“1,645cm-1 can be attributed to the -NH bending vibration Figure 3.”
Yakar 和 Dede - 2022 - Production and Characterization of Healing Polymer DOI: 10.3389/fmats.2022.910761
এই ব্যান্ডের সাথে একটি স্পেকট্রাম আছে?
আপনার FTIR স্পেকট্রাম আপলোড করুন এবং সেকেন্ডের মধ্যে একটি সম্পূর্ণ ব্যাখ্যা রিপোর্ট পান — সাহিত্য সাইটেশন সহ পিক অ্যাসাইনমেন্ট, লাইব্রেরি ম্যাচ এবং একটি আত্মবিশ্বাস-রেটেড এভিডেন্স চেইন।