The estimation of halobenzenes aroma ticity using NBO calculations

Since ۱۴۰ years ago, which w as introduced the conce pt of aroma ticity by Ke kule, aroma ticity has b een an interesting phenomenon in current che mistry. Che mists are tr ying to prov ide a clear definition and calculation for aromaticity. Although the most popu lar definition of aromaticity to be found in standard chemistry textboo ks is electro nic cyclic delocalization, but the problem is th at the arom aticity is a multidimensional pro perty and cannot be de fined precisely [۱]. So, different q uantitative c riteria inclu ding geom etric, energetic and ma gnetic indices are used in the estimation of aromaticity. S ome methods based on these criteria are averag e two center index (AT I), aromatic stabilization energy (A SE), and ha rmonic osci llator model of aromatic ity (HOMA ) [۲]. In thi s work, the aromaticity of benzene r ing with ele ctron attractive substitutions has been estimat ed using th e results of natural bon d orbital ( NBO) analysis. The results have been evaluated by ASE and ATI indices of aromaticity.

کلیدواژه ها:

Aromaticity ، Electrondelocalization ، ATI ، NBO