“
The structural stabilities and electronic properties of C20 fullerene and some its incorporated boron and nitrogen derivatives
are probed at B3LYP/AUG-cc-pVTZ level of theory. According to density functional theory results, the topology of inserted B
or N heteroatoms in [20]-fullerene perturbs strongly the stability, energy, geometry, charge, polarity, nucleus-independent
chemical shifts, aromaticity, and highest-occupied molecular orbital and lowest-unoccupied molecular orbital (HOMO–LUMO)
gap of the resulting heterofullerenes. Vibrational frequency (υmin) calculations show that except N1020-(b+n)heterofullerenes with b, and n = 0, 4, 5, 8, and 10 are true minima. The calculated band gaps (ΔE, andN8C(2.86 eV), show them the most stable heterofullerenes against electronic excitations. While 10 B substituting in equatorial
position increase the conductivity of B
12
10
C
through decreasing its band gaps, 10 N doping in equatorial position enhance
stability of N10C1010 against electronic excitations via increasing its band gaps. High natural bond orbital and Mulliken
charge transfer on the surfaces of B atoms, especially B5N5C
with five B–N bonds in the equatorial position, provokes further
investigation on its possible application for hydrogen storage. Nucleus-independent chemical shift values show that B10 is the most aromatic species. The calculated heat of atomization per carbon (ΔHat/C) of B8C shows it the most thermodynamic stable heterofullerenes of each..
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Dr. Somayeh Soleimani
Karaj Islamic Azad University