Theoretical and experimental electrostatic potential around the m-nitrophenol molecule.
Mokhtaria Drissi1, Nadia Benhalima2, Youcef Megrouss3
1Laboratoire LTPS, Faculté des Sciences et de la Technologie, Université de Mostaganem, 27000-Mostaganem, Algeria. mokadrissi@gmail.com.
Molecules (Basel, Switzerland)
|March 6, 2015
Summary
This study compares experimental and theoretical electron charge density in m-nitrophenol (m-NPH). Results show good agreement between methods, confirming molecular properties and intramolecular charge transfer.
Area of Science:
- Quantum Chemistry
- Crystallography
- Molecular Physics
Background:
- m-Nitrophenol (m-NPH) exhibits unique physical properties.
- Accurate electron charge density distribution is crucial for understanding molecular behavior.
Purpose of the Study:
- To compare experimental and theoretical electron charge density and electrostatic potential of m-NPH.
- To validate theoretical methods against experimental data for molecular properties.
Main Methods:
- High-resolution X-ray diffraction for experimental data.
- Density Functional Theory (DFT) at B3LYP/6-31G* level using Gaussian for theoretical calculations.
- Hansen and Coppens multipolar model for experimental charge density analysis.
Main Results:
- Experimental and theoretical electron charge densities were compared.
- Electrostatic potential and dipole moment calculations showed good agreement between methods.
- Intramolecular charge transfer was confirmed via Highest Occupied Molecular Orbital-Lowest Unoccupied Molecular Orbital (HOMO-LUMO) analysis.
Conclusions:
- DFT calculations provide a reliable method for determining m-NPH's electron charge density and electrostatic potential.
- Experimental and theoretical approaches are complementary for characterizing molecular properties.
- The study validates the use of computational methods in predicting molecular characteristics.
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