of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy AB INITIO DENSITY FUNCTIONAL THEORY By Igor Vitalyevich Schweigert August 2005 Chair: Rodney J. Bartlett Major Department: Chemistry Ab initio Density Functional Theory (DFT) is a new approach to the electronic structure problem that com...

In this study the chemical properties of B6C4Si and C16 Clusters connected vitamin C have been investigated using density functional theory (DFT). NMR parameters and HOMO- LUMO Gap energy are calculated by using density functional method (B3LYP) with 6-311G* basis set. Calculations show that HOMO- LUMO Gap energy of vitamin C decreases after connecting to B6C4Si or C16 cluster decreasing of HOM...

in this work, we report results of calculations based on the density functional theory of different species metal-ozone, containing mercury, silver and gold. the chosen species range from small molecules and large transition-metal containing ozone with mercury, silver and gold complexes. a comparative analysis of the description of the metal-oxygen bond obtained by different methodologies is pr...

Detailed physisorption data from experiment for the H(2) molecule on low-index Cu surfaces challenge theory. Recently, density functional theory (DFT) has been developed to account for nonlocal correlation effects, including van der Waals (dispersion) forces. We show that the functional vdW-DF2 gives a potential-energy curve, potential-well energy levels and difference in lateral corrugation pr...

The electronic and structural properties of single wall carbon nanotubes (SWCNTs) interacted with 4-amino phenyl-azobenzene were theoretically investigated by using the hybrid DFT (hybrid-density functional theory) calculations. The amount of thermodynamic parameters of this reaction in the gas and aqueous phase suggesting thermodynamic favourability for adsorption of 4-amino phenyl-azobenzene ...

the effect of impurities on quantum chemical parameters of single-walled nanotubes (swnts) was studied using density functional theory (dft). the density of states (dos), fermi energy and thermodynamic energies of (5,5) carbon nanotubes were calculated in the presence of nitrogen impurity. it was found that this nanotube remains metallic after being doped with one nitrogen atom. the partial den...

Electronic structure calculations are now indispensible for understanding chemical phenomena. Density functional theory (DFT), which is simple, conceptual, and applicable to large systems, has emerged as a powerful computational tool to tackle molecular electronic structures. DFT efficiently calculates electronic structure with high accuracy, and its algorithm is suitable for parallel computing...

Tetrazole-containing compounds have been the subject of much recent research because of theirpotential as high energy density materials (HEDMs). In this work, theoretical studies on the 1Htetrazolylderivatives of tetrahedrane were done at the density functional theory (DFT) method withthe 6-31G(d) basis set without any symmetrical restrictions in order to find the structural andenergetically pr...

The doublet and quartet potential energy surfaces for the Ti++C2H6→TiC2H+4+H2 and Ti++C2H6→TiCH+2+CH4reactions are studied using density functional theory(DFT) with the B3LYP functional and ab initiocoupled cluster CCSD(T) methods with high quality basis sets. Structures have been optimized at the DFT level and the minima connected to each transition state (TS) by following the intrinsic reacti...

The electronic and structural properties of single wall carbon nanotubes (SWCNTs) interacted with 4-amino phenyl-azobenzene were theoretically investigated by using the hybrid DFT (hybrid-density functional theory) calculations. The amount of thermodynamic parameters of this reaction in the gas and aqueous phase suggesting thermodynamic favourability for adsorption of 4-amino phenyl-azobenzene ...