Noncovalent Interactions in Fullerene-like Derivatives: Endohedral Confinement of Noble Gas Atoms Pnicogen Bonds Noncovalent Interactions in Fullerene-like Derivatives: Endohedral Confinement of Noble Gas Atoms Pnicogen Bonds

تعداد82 صفحه در فایل word

1. Sc. Thesis in

Physical Chemistry

Noncovalent Interactions in Fullerene-like Derivatives:

1. Endohedral Confinement of Noble Gas Atoms

2. Pnicogen Bonds

Noncovalent Interactions in Fullerene-like Derivatives:

1. Endohedral Confinement of Noble Gas Atoms

2. Pnicogen Bonds

In the first part of present thesis, the encapsulation of noble gas atoms, Ng=He-Xe, in the stable heterofullerene structures X₁₂Y₁₂ (X=B, Al and Y=N, P) , Ng@ X₁₂Y₁₂ is studied. The calculated binding energies for all Ng@X₁₂Y₁₂ complexes are positive which indicates repulsive interaction between the two species. In the second part, stability, geometry and electronic structure of the C₃₀X₁₅Y₁₅ (X=B, Al and Y=N, P) nanocages are compared. Formation energies and HOMO-LUMO gaps for series of XY-substituted C₆₀ fullerenes have been systematically investigated via M05-2X functional combined with the 6–31G basis set. The results show that the larger band gaps and formation energies relate to nitrogen containing cages, C₃₀B₁₅N₁₅ and C₃₀Al₁₅N₁₅. The endohedral complexes of H_nYF_3-n, (Y=N, P and n=1, 2) with C₃₀B₁₅N₁₅ and C₃₀Al₁₅N₁₅ have been computationally characterized. The binding energies, equilibrium geometries and harmonic vibrational frequencies of these complexes have been calculated. It was found that all guest molecules are stabilized inside the nanocages and the geometries are not perturbed significantly upon encapsulation. The nature of the pnicogen interactions, N···N and P···N, and the charge transfer from the guest molecules to cages have been studied by using the quantum theory of atoms in molecules and natural bond orbital analyses.

Keyword: Heterofullerene, Noble gas atom, pnicogen interaction