**Peak Assignments (based on standard FTIR wavenumber ranges):**
- **694 cm⁻¹ (weak, broad):** C-H out-of-plane bending (aromatic ring, monosubstituted or meta-disubstituted) or C=C bending (alkene). - **812 cm⁻¹ (weak, sharp):** C-H out-of-plane bending (para-disubstituted aromatic ring or 1,2,4-trisubstituted). - **1245 cm⁻¹ (weak, sharp):** C-O stretching (ether, ester, or alcohol) or C-N stretching (amine/amide). - **1358 cm⁻¹ (weak, broad):** C-H bending (methyl or methylene) or O-H bending (phenol). - **1410 cm⁻¹ (weak, sharp):** C-H bending (methyl or methylene) or aromatic ring stretching (semicircle). - **1514 cm⁻¹ (weak, sharp):** Aromatic C=C stretching (ring quadrant, typical for para-substituted benzene). - **1552 cm⁻¹ (strong, broad):** N-O asymmetric stretching (nitro compound) or C=C stretching (conjugated alkene) or amide II (N-H bending + C-N stretching). - **1608 cm⁻¹ (medium, sharp):** Aromatic C=C stretching (ring quadrant, typical for conjugated system). - **1653 cm⁻¹ (strong, broad):** C=O stretching (amide I, conjugated ketone, or carboxylic acid) or C=C stretching (conjugated alkene). - **3310 cm⁻¹ (medium, broad):** N-H stretching (secondary amine or amide, hydrogen-bonded) or O-H stretching (hydrogen-bonded alcohol/phenol). - **3424 cm⁻¹ (medium, broad):** O-H stretching (hydrogen-bonded) or N-H stretching (primary amine or amide, asymmetric).
**Functional Groups Identified (data-supported):**
- **Aromatic ring:** Confirmed by 694, 812, 1410, 1514, 1608 cm⁻¹ peaks. - **Carbonyl (C=O):** Confirmed by 1653 cm⁻¹ (strong, broad). - **Amide or amine:** Confirmed by 3310, 3424 cm⁻¹ (N-H stretching) and 1552 cm⁻¹ (amide II). - **Ether or alcohol:** Suggested by 1245 cm⁻¹ (C-O stretching) and broad O-H/N-H bands. - **Possible nitro group:** Suggested by 1552 cm⁻¹ (strong, broad N-O stretch), but not definitive due to overlap with amide II.
**Conclusion (data-supported):**
The sample contains an aromatic ring (para-substituted or 1,2,4-trisubstituted), a carbonyl group (likely amide I), and N-H groups (amide or amine). The strong broad peak at 1653 cm⁻¹ and the N-H stretching bands at 3310/3424 cm⁻¹ are consistent with an **amide functional group**. The presence of a C-O stretch at 1245 cm⁻¹ suggests an ether or alcohol moiety.
**Inference (experience-based):**
【Inference】Based on the combination of aromatic C=C (1514, 1608 cm⁻¹), strong amide I (1653 cm⁻¹), amide II (1552 cm⁻¹), and N-H stretching (3310, 3424 cm⁻¹), the compound is likely a **para-substituted aromatic amide** (e.g., a benzamide derivative). The weak sharp peak at 812 cm⁻¹ supports para-substitution. The broad O-H/N-H bands and C-O stretch may indicate a hydroxyl or ether substituent on the aromatic ring. The low similarity (0.734) to (4-ethoxyphenyl)urea suggests the structure differs in substitution pattern or functional group (e.g., amide vs. urea).
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 → Conclusion/Inference**
**Peak Assignments (based on standard FTIR wavenumber ranges):**
- **694 cm⁻¹ (weak, broad):** C-H out-of-plane bending (aromatic ring, monosubstituted or meta-disubstituted) or C=C bending (alkene).
- **812 cm⁻¹ (weak, sharp):** C-H out-of-plane bending (para-disubstituted aromatic ring or 1,2,4-trisubstituted).
- **1245 cm⁻¹ (weak, sharp):** C-O stretching (ether, ester, or alcohol) or C-N stretching (amine/amide).
- **1358 cm⁻¹ (weak, broad):** C-H bending (methyl or methylene) or O-H bending (phenol).
- **1410 cm⁻¹ (weak, sharp):** C-H bending (methyl or methylene) or aromatic ring stretching (semicircle).
- **1514 cm⁻¹ (weak, sharp):** Aromatic C=C stretching (ring quadrant, typical for para-substituted benzene).
- **1552 cm⁻¹ (strong, broad):** N-O asymmetric stretching (nitro compound) or C=C stretching (conjugated alkene) or amide II (N-H bending + C-N stretching).
- **1608 cm⁻¹ (medium, sharp):** Aromatic C=C stretching (ring quadrant, typical for conjugated system).
- **1653 cm⁻¹ (strong, broad):** C=O stretching (amide I, conjugated ketone, or carboxylic acid) or C=C stretching (conjugated alkene).
- **3310 cm⁻¹ (medium, broad):** N-H stretching (secondary amine or amide, hydrogen-bonded) or O-H stretching (hydrogen-bonded alcohol/phenol).
- **3424 cm⁻¹ (medium, broad):** O-H stretching (hydrogen-bonded) or N-H stretching (primary amine or amide, asymmetric).
**Functional Groups Identified (data-supported):**
- **Aromatic ring:** Confirmed by 694, 812, 1410, 1514, 1608 cm⁻¹ peaks.
- **Carbonyl (C=O):** Confirmed by 1653 cm⁻¹ (strong, broad).
- **Amide or amine:** Confirmed by 3310, 3424 cm⁻¹ (N-H stretching) and 1552 cm⁻¹ (amide II).
- **Ether or alcohol:** Suggested by 1245 cm⁻¹ (C-O stretching) and broad O-H/N-H bands.
- **Possible nitro group:** Suggested by 1552 cm⁻¹ (strong, broad N-O stretch), but not definitive due to overlap with amide II.
**Conclusion (data-supported):**
The sample contains an aromatic ring (para-substituted or 1,2,4-trisubstituted), a carbonyl group (likely amide I), and N-H groups (amide or amine). The strong broad peak at 1653 cm⁻¹ and the N-H stretching bands at 3310/3424 cm⁻¹ are consistent with an **amide functional group**. The presence of a C-O stretch at 1245 cm⁻¹ suggests an ether or alcohol moiety.
**Inference (experience-based):**
【Inference】Based on the combination of aromatic C=C (1514, 1608 cm⁻¹), strong amide I (1653 cm⁻¹), amide II (1552 cm⁻¹), and N-H stretching (3310, 3424 cm⁻¹), the compound is likely a **para-substituted aromatic amide** (e.g., a benzamide derivative). The weak sharp peak at 812 cm⁻¹ supports para-substitution. The broad O-H/N-H bands and C-O stretch may indicate a hydroxyl or ether substituent on the aromatic ring. The low similarity (0.734) to (4-ethoxyphenyl)urea suggests the structure differs in substitution pattern or functional group (e.g., amide vs. urea).
This discussion presents an infrared spectral analysis combining automated interpretation with reference comparison to support functional group identification and structural assessment.