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Spectroscopic analysis of cinnamic acid using quantum chemical calculations
K S Vinod1, S Periandy2, M Govindarajan3
1Department of Physics, Indira Gandhi Polytechnic College, Mahe, UT-Puducherry, India; Research Scholar, Bharathiar University, Coimbatore, Tamil Nadu, India.
Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
|October 16, 2014
Summary
This study analyzes cinnamic acid
Area of Science:
- Computational chemistry
- Molecular spectroscopy
Background:
- Cinnamic acid is a key organic compound with diverse applications.
- Understanding its molecular properties is crucial for various scientific fields.
Purpose of the Study:
- To conduct a comprehensive vibrational and spectroscopic analysis of cinnamic acid.
- To investigate its electronic, optical, and molecular properties using computational methods.
Main Methods:
- Fourier Transform Infrared (FT-IR) and FT-Raman spectroscopy.
- Nuclear Magnetic Resonance (NMR) spectroscopy ((13)C and (1)H).
- High-Frequency (HF) and Density Functional Theory (DFT) calculations (B3LYP).
- Gauge-Independent Atomic Orbital (GIAO) method for chemical shifts.
Main Results:
- Observed and computed vibrational frequencies were assigned and compared.
- Electronic properties including absorption wavelengths, excitation energy, and dipole moment were determined.
- Frontier molecular orbital energies, Mulliken charges, and UV-Vis spectra were calculated.
- Molecular electrostatic potential (MEP) surface was constructed.
Conclusions:
- The study provides a detailed assignment of vibrational modes for cinnamic acid.
- Computational methods accurately predict experimental spectroscopic data.
- The electronic and optical properties offer insights into cinnamic acid's behavior and potential applications.
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