Vibrational spectroscopy and density functional theory study of 4-mercaptophenol

Area of Science:

• Computational chemistry
• Molecular spectroscopy
• Quantum chemistry

Background:

• 4-mercaptophenol (4-MPH) is a model molecule used for structural analysis.
• Understanding molecular structure is crucial in various chemical disciplines.

Purpose of the Study:

• To theoretically predict and experimentally validate the IR and Raman spectra of 4-MPH.
• To assign molecular vibrational bands using DFT calculations.
• To investigate the molecular electrostatic potential and HOMO-LUMO gap of 4-MPH.

Main Methods:

• Density Functional Theory (DFT) calculations at the B3LYP/6-311+G(**) level.
• Experimental acquisition of Fourier Transform Infrared (FTIR) and Raman spectra.
• Molecular electrostatic potential surface calculations.
• HOMO-LUMO gap determination.

Main Results:

• Predicted IR and Raman spectra aligned well with experimental data.
• All experimental spectral bands were assigned based on DFT modeling.
• Molecular electrostatic potential indicated 4-MPH as having two hydrogen bond donors and three acceptors.
• Theoretical HOMO-LUMO gap was determined.

Conclusions:

• The study successfully validated DFT methods for predicting 4-MPH spectra.
• The findings provide a comprehensive understanding of 4-MPH's structural and electronic properties.
• This work serves as a reference for future studies involving 4-MPH and similar molecules.