Density functional theory (DFT) investigation of molecular structure and frontier molecular orbitals (FMOs) of P-N,N-dimethylaminobenzylidenemalononitrile (DBM)

M M El-Nahass; M A Kamel; A F El-Deeb; A A Atta; S Y Huthaily

doi:10.1016/j.saa.2011.05.006

Density functional theory (DFT) investigation of molecular structure and frontier molecular orbitals (FMOs) of P-N,N-dimethylaminobenzylidenemalononitrile (DBM)

Spectrochim Acta A Mol Biomol Spectrosc. 2011 Sep;79(5):1499-504. doi: 10.1016/j.saa.2011.05.006. Epub 2011 May 12.

Authors

M M El-Nahass¹, M A Kamel, A F El-Deeb, A A Atta, S Y Huthaily

Affiliation

¹ Physics Department, Faculty of Education, Ain Shams University, Roxy, 11757 Cairo, Egypt.

PMID: 21640638
DOI: 10.1016/j.saa.2011.05.006

Abstract

P-N,N-dimethylaminobenzylidenemalononitrile (DBM) dye belongs to a class of organic compounds known as molecular rotors. Its optimized geometry and frontier molecular orbitals (FMOs), before and after ultraviolet (UV) irradiation, were obtained by DFT/B3LYP level with complete relaxation in the potential energy surface using 6-311++G(d,p) basis set. It is found that the length of C-C bonds of the DBM molecule increases after the UV irradiation, which leads to an increase in its dipole moment making it as a promising material for solar cell applications. Also, its HOMO-LUMO gap decreased from 3.46 to 3.34 eV. From the cyclic voltammetry measurements the value of HOMO-LUMO gap is equal to 3.21 eV. This means that B3LYP/6-311++G(d,p) level of theory is the best one for calculations.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Benzylidene Compounds / chemistry*
Magnetic Resonance Spectroscopy
Models, Chemical*
Models, Molecular
Models, Theoretical*
Molecular Structure
Nitriles / chemistry*
Quantum Theory

Substances

Benzylidene Compounds
Nitriles
P-N,N-dimethylaminobenzylidenemalononitrile