Investigation of HMO spectra of Huckel and Mobius type cyclacenes

Turker, L
Erkoç, Şakir
The Huckel molecular orbital spectra (HMO) of Huckel- and Mobius-type cyclacenes having 3-15 benzenoid rings were investigated and it was found that certain eigenvalues are topologically invariant, whereas others exhibit topological periodicity. Fbr example, Huckel-type cyclacenes having 2r (r: 2,3,4,...) benzenoid rings which possess nonbonding molecular orbitals (NBMO) and are thus expected to be open shell structures.


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Density functional theory calculations were used to study the adsorption of three transition metal atoms (Fe, Co, and Ni) on the external surface of two zigzag and two armchair graphyne nanotubes. The most stable position for the adsorption of all three metal atoms on all nanotubes is on the acetylenic ring. The metal atom remains in the plane of the acetylenic ring and makes six bonds with neighboring carbon atoms. Fe and Co complexes are magnetic and show different properties such as metal, semimetal, hal...
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Early development of spinodal instabilities and density correlation functions in asymmetric nuclear matter are investigated in the stochastic extension of the Walecka-type relativistic mean field including coupling with rho meson. Calculations are performed under typical conditions encountered in heavy-ion collisions and in the crusts of neutron stars. In general, growth of instabilities occur relatively slower for increasing charge asymmetry of matter. At higher densities around rho = 0.4 rho(0) fluctuatio...
Citation Formats
L. Turker and Ş. Erkoç, “Investigation of HMO spectra of Huckel and Mobius type cyclacenes,” TURKISH JOURNAL OF CHEMISTRY, pp. 167–172, 1997, Accessed: 00, 2020. [Online]. Available: