The shell structure of pi ring currents in the expanded porphyrin amethyrin.
نویسندگان
چکیده
Direct ab initio mapping of induced current density in the pi system of the expanded porphyrin amethyrin shows a picture at variance with the conventional 4npi ascription of antiaromaticity. The ipsocentric orbital model interprets the pattern of currents as a superposition of shell contributions: an intense paratropic ring current concentrated on the inner 20-site cycle, counteracted by a weaker diatropic circulation on a 24-site conjugation pathway and a combination of local 5-site diatropic circulations on the six pyrrolic rings.
منابع مشابه
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عنوان ژورنال:
- Organic & biomolecular chemistry
دوره 4 12 شماره
صفحات -
تاریخ انتشار 2006