**Data:** The FTIR spectrum exhibits numerous strong, sharp absorption bands across a wide range (724–3892 cm⁻¹). Key regions include: * **724, 748, 891, 983 cm⁻¹**: Weak bands. * **1237–1688 cm⁻¹**: Medium-intensity bands, including sharp peaks at 1280, 1378, 1515, 1628, 1785, 1815 cm⁻¹ and a broad band at 1688 cm⁻¹. * **1952–2671 cm⁻¹**: A dense series of very strong, sharp bands (e.g., 1952, 2002, 2027, 2125, 2154, 2258, 2335, 2353, 2471, 2495, 2564, 2586, 2632, 2650, 2671 cm⁻¹) interspersed with strong broad bands (e.g., 2210, 2308, 2711, 2750, 2787 cm⁻¹). * **2808–3892 cm⁻¹**: A very dense forest of very strong, sharp, and broad bands dominating the high-wavenumber region. Notable clusters are around 2808–2944 cm⁻¹ (strong), 2990–3110 cm⁻¹ (very strong), and an extensive series from 3125 cm⁻¹ to 3892 cm⁻¹ (all very strong).
**Analysis:** * **724–983 cm⁻¹**: Weak bands may correspond to C–H out-of-plane bending (aromatics, ~700-900 cm⁻¹) or C–C skeletal vibrations. Data is insufficient for definitive assignment. * **1237–1688 cm⁻¹**: * 1378 cm⁻¹: Symmetric CH₃ bending. * 1464 cm⁻¹: Asymmetric CH₂/CH₃ bending. * 1499, 1515 cm⁻¹: Aromatic C=C stretching or N–H bending (amines/amides). * 1628 cm⁻¹: C=C stretching (conjugated/aromatic) or N–H bending (primary amines). * 1688 cm⁻¹ (broad): Typical for C=O stretching of carboxylic acids, amides (amide I), or conjugated ketones. * 1785, 1815 cm⁻¹: Characteristic of C=O stretching in acid anhydrides (two bands), imides, or highly strained cyclic ketones. * **1952–2671 cm⁻¹**: This pattern is highly atypical for common organic functional groups. The multitude of very strong, sharp bands suggests: * **[Inference]** Possible overtones and combination bands from fundamental vibrations below 2000 cm⁻¹, amplified by high concentration or specific molecular symmetry. * **[Inference]** Potential presence of specific inorganic anions (e.g., cyanate, thiocyanate, azide) or metal-ligand vibrations, but exact assignments require reference data for specific salts/coordination compounds. * Bands at 2125, 2154, 2210, 2258 cm⁻¹ could indicate nitrile (C≡N), isocyanate (-N=C=O), or acetylide (C≡C) stretches, but their co-occurrence with dozens of other strong peaks is unusual for simple organics. * Bands at 2335, 2353 cm⁻¹ are characteristic of atmospheric CO₂ and are likely an artifact. * **2808–3892 cm⁻¹**: * 2808–2944 cm⁻¹: C–H stretching (alkanes). * 2990–3110 cm⁻¹: =C–H stretching (alkenes, aromatics). * **3125–3600+ cm⁻¹**: The extraordinary density and strength of bands in this region overwhelmingly indicate extensive hydrogen-bonded **O–H and/or N–H stretching vibrations**. This includes: * Broad bands (~3200–3550 cm⁻¹): Strongly hydrogen-bonded O–H (acids, alcohols), N–H (amines, amides). * Sharp bands intermixed: Possibly "free" or weakly H-bonded O–H/N–H, or Fermi resonances. * **3611–3892 cm⁻¹**: Very strong, sharp/broad bands extending beyond 3600 cm⁻¹ suggest the presence of **free O–H stretches** (alcohols, phenols) and potentially **N–H stretches of primary amines** (~3300-3500 cm⁻¹, likely obscured). Bands above 3700 cm⁻¹ are particularly indicative of free, non-H-bonded O–H groups.
**Conclusions/Inferences:** 1. The sample is **not a simple organic compound**. The spectrum is exceptionally complex, indicating a mixture, a polymeric material, or a compound with high symmetry and/or extensive vibrational coupling. 2. **Definitively indicated functional groups/features:** * **O–H groups**: Present extensively, evidenced by the very strong, broad hydrogen-bonded O–H stretches (3200–3550 cm⁻¹) and sharp free O–H stretches (>3600 cm⁻¹). * **C–H groups**: Present as aliphatic (2808–2944 cm⁻¹) and unsaturated/aromatic (2990–3110 cm⁻¹) types. * **Carbonyl (C=O) groups**: Indicated by bands at 1688 cm
This discussion presents an infrared spectral analysis combining
automated interpretation with reference comparison to support
functional group identification and structural assessment.
FTIR Spectrum Interpretation Summary
Comparative Analysis Conclusion
AI-assisted Interpretation Conclusion
**Data → Analysis → Conclusions/Inferences**
**Data:**
The FTIR spectrum exhibits numerous strong, sharp absorption bands across a wide range (724–3892 cm⁻¹). Key regions include:
* **724, 748, 891, 983 cm⁻¹**: Weak bands.
* **1237–1688 cm⁻¹**: Medium-intensity bands, including sharp peaks at 1280, 1378, 1515, 1628, 1785, 1815 cm⁻¹ and a broad band at 1688 cm⁻¹.
* **1952–2671 cm⁻¹**: A dense series of very strong, sharp bands (e.g., 1952, 2002, 2027, 2125, 2154, 2258, 2335, 2353, 2471, 2495, 2564, 2586, 2632, 2650, 2671 cm⁻¹) interspersed with strong broad bands (e.g., 2210, 2308, 2711, 2750, 2787 cm⁻¹).
* **2808–3892 cm⁻¹**: A very dense forest of very strong, sharp, and broad bands dominating the high-wavenumber region. Notable clusters are around 2808–2944 cm⁻¹ (strong), 2990–3110 cm⁻¹ (very strong), and an extensive series from 3125 cm⁻¹ to 3892 cm⁻¹ (all very strong).
**Analysis:**
* **724–983 cm⁻¹**: Weak bands may correspond to C–H out-of-plane bending (aromatics, ~700-900 cm⁻¹) or C–C skeletal vibrations. Data is insufficient for definitive assignment.
* **1237–1688 cm⁻¹**:
* 1378 cm⁻¹: Symmetric CH₃ bending.
* 1464 cm⁻¹: Asymmetric CH₂/CH₃ bending.
* 1499, 1515 cm⁻¹: Aromatic C=C stretching or N–H bending (amines/amides).
* 1628 cm⁻¹: C=C stretching (conjugated/aromatic) or N–H bending (primary amines).
* 1688 cm⁻¹ (broad): Typical for C=O stretching of carboxylic acids, amides (amide I), or conjugated ketones.
* 1785, 1815 cm⁻¹: Characteristic of C=O stretching in acid anhydrides (two bands), imides, or highly strained cyclic ketones.
* **1952–2671 cm⁻¹**: This pattern is highly atypical for common organic functional groups. The multitude of very strong, sharp bands suggests:
* **[Inference]** Possible overtones and combination bands from fundamental vibrations below 2000 cm⁻¹, amplified by high concentration or specific molecular symmetry.
* **[Inference]** Potential presence of specific inorganic anions (e.g., cyanate, thiocyanate, azide) or metal-ligand vibrations, but exact assignments require reference data for specific salts/coordination compounds.
* Bands at 2125, 2154, 2210, 2258 cm⁻¹ could indicate nitrile (C≡N), isocyanate (-N=C=O), or acetylide (C≡C) stretches, but their co-occurrence with dozens of other strong peaks is unusual for simple organics.
* Bands at 2335, 2353 cm⁻¹ are characteristic of atmospheric CO₂ and are likely an artifact.
* **2808–3892 cm⁻¹**:
* 2808–2944 cm⁻¹: C–H stretching (alkanes).
* 2990–3110 cm⁻¹: =C–H stretching (alkenes, aromatics).
* **3125–3600+ cm⁻¹**: The extraordinary density and strength of bands in this region overwhelmingly indicate extensive hydrogen-bonded **O–H and/or N–H stretching vibrations**. This includes:
* Broad bands (~3200–3550 cm⁻¹): Strongly hydrogen-bonded O–H (acids, alcohols), N–H (amines, amides).
* Sharp bands intermixed: Possibly "free" or weakly H-bonded O–H/N–H, or Fermi resonances.
* **3611–3892 cm⁻¹**: Very strong, sharp/broad bands extending beyond 3600 cm⁻¹ suggest the presence of **free O–H stretches** (alcohols, phenols) and potentially **N–H stretches of primary amines** (~3300-3500 cm⁻¹, likely obscured). Bands above 3700 cm⁻¹ are particularly indicative of free, non-H-bonded O–H groups.
**Conclusions/Inferences:**
1. The sample is **not a simple organic compound**. The spectrum is exceptionally complex, indicating a mixture, a polymeric material, or a compound with high symmetry and/or extensive vibrational coupling.
2. **Definitively indicated functional groups/features:**
* **O–H groups**: Present extensively, evidenced by the very strong, broad hydrogen-bonded O–H stretches (3200–3550 cm⁻¹) and sharp free O–H stretches (>3600 cm⁻¹).
* **C–H groups**: Present as aliphatic (2808–2944 cm⁻¹) and unsaturated/aromatic (2990–3110 cm⁻¹) types.
* **Carbonyl (C=O) groups**: Indicated by bands at 1688 cm
This discussion presents an infrared spectral analysis combining automated interpretation with reference comparison to support functional group identification and structural assessment.