Ab-initio and DFT calculations on molecular structure, NBO, HOMO-LUMO study and a new vibrational analysis of 4-(Dimethylamino) Benzaldehyde

ROCHA, MARIANA; DI SANTO, ALEJANDRO; ARIAS, JUAN MARCELO; GIL, DIEGO; BEN ALTABEF, AIDA

SPECTROCHIMICA ACTA A: MOLECULAR AND BIOMOLECULAR SPECTROSCOPY

ELSEVIER

Lugar: Amsterdam; Año: 2014

0584-8539

The experimental and theoretical study on the molecular structure and a new vibrational analysis of 4-(Dimethylamino) Benzaldehyde (DMABA) is presented. The IR and Raman spectra were recorded in solidstate. Optimized geometry, vibrational frequencies and various thermodynamic parameters of the titlecompound were calculated using DFT methods and are in agreement with the experimental values. Adetailed interpretation of the IR and Raman spectra of the title compound were reported. The stabilityof the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzedusing NBO analysis and AIM approach. The HOMO and LUMO analysis were used to determine the chargetransfer within the molecule and some molecular properties such as ionization potential, electron affinity,electronegativity, chemical potential, hardness, softness and global electrophilicity index. The TD-DFTapproach was applied to assign the electronic transitions observed in the UV?visible spectrum measuredexperimentally. Molecular electrostatic potential map was performed by the DFT method. According toDSC measurements, the substance presents a melting point of 72.34 C and decomposes at temperatureshigher than 193 C. 2014 Elsevier B.V. All rights reserved.