The aromaticity of the dianion (2) and the antiaromaticity of the dication (3) of tetrabenzo[5.5]fulvalene have been evaluated through magnetic criteria, (1)H NMR shifts, nucleus-independent chemical shifts, NICS, and magnetic susceptibility exaltation, Lambda. The sum of the NICS values, using the GIAO (gauge-independent atomic orbital) method, for 2 is -35.2; that of 3 is +38.2, indicating th...

Natural organic matter (NOM) was concentrated from various sites across Canada using a portable reverse-osmosis unit to obtain a range of NOM types, from mainly allochthonous (terrestrially derived) to mainly autochthonous (aquatically derived) NOM. The addition of NOM to Cu exposures in ion-poor water always decreased Cu toxicity to rainbow trout (Oncorhynchus mykiss, approximately 1 g) over a...

Ayub, R. 2017. Excited State Aromaticity and Antiaromaticity. Fundamental Studies and Applications. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1594. 61 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-513-0138-9. The central theme of this thesis is the ability to tune various molecular properties by controlling and utilizing aroma...

Besides the most common form of aromaticity involving a π-ring, hexaiodobenzene and hexakis(phenylselenyl)benzene dications also present σ-aromaticity in outer ring formed by main group substituents. These two compounds are considered σ- π-double aromatic, their characterization is special interest to fields organic structural chemistry. In this work, we decided explore double substituted tropy...

Cyclooctatetraene (COT), the first 4nπ-electron system to be studied, adopts an inherently nonplanar tub-shaped geometry of D2d symmetry with alternating single and double bonds, and hence behaves as a nonaromatic polyene rather than an antiaromatic compound. Recently, however, considerable 8π-antiaromatic paratropicity has been shown to be generated in planar COT rings even with the bond alter...