A DENSITY FUNCTIONAL THEORY STUDY OF GEOMETRICAL AND ELECTRONIC PROPERTIES OF FERROCENE AND ACETYL FERROCENE

Abstract

Studies on substituted ferrocenes, acetyl ferrocene in particular, are very limited. So the geometrical and electrical
properties of ferrocene and acetyl ferrocene are studied using Density Functional Theory (DFT) with particular emphasis
on Natural Bond Orbital (NBO) and Time Dependent Density Functional Theory (TDDFT) analysis. In the gas phase the
eclipsed conformer is found to be more stable than the corresponding staggered conformer for both the title compounds.
Mulliken charge analysis is carried out to identify the distribution of atomic charge on various atoms of both the
molecules. From the Frontier Molecular Orbital (FMO) analysis, the HOMO-LUMO energy gaps of the eclipsed
conformers of ferrocene and acetyl ferrocene are calculated as 5.42 and 4.62 eV respectively. Molecular electrostatic
potential (MEP) is used to identify the potential active sites which are susceptible to nucleophilic and electrophilic
attacks. Natural population analysis is carried out to find the distribution of electrons in the core, valence and Rydberg
sub-shells of both compounds. Thus NBO analysis provides useful information regarding intra- and intermolecular
bonding and interactions among various bonds within the molecule. Finally TDDFT calculations are performed and UVVIS spectra are simulated. This helps us to identify the important electronic transitions between various energy levels.
This study provides a better understanding of the charge delocalization process and electronic properties of ferrocene and
acetyl ferrocene to a greater extent.