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Toward a Generalized Huckel Rule: The Electronic Structure of Carbon Nanocones.

ABSTRACT: In this work, we investigate a particular class of carbon nanocones, which we name graphannulenes, and present a generalized Hückel rule (GHR) that predicts the character of their ground state based on simply the three topological indices that uniquely define them. Importantly, this rule applies to both flat and curved systems, encompassing a wide variety of known structures that do not satisfy the "classic" 4n + 2 rule such as coronene, corannulene, and Kekulene. We test this rule at the Hückel level of theory for a large number of systems, including structures that are convex and flat, with a saddle-like geometry, and at the CASSCF level of theory for a selected representative subset. All the performed calculations support the GHR that we propose in this work.

SUBMITTER: Apriliyanto YB

PROVIDER: S-EPMC8607423 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Toward a Generalized Hückel Rule: The Electronic Structure of Carbon Nanocones.

Apriliyanto Yusuf Bramastya YB Battaglia Stefano S Evangelisti Stefano S Faginas-Lago Noelia N Leininger Thierry T Lombardi Andrea A

The journal of physical chemistry. A 20211104 45

In this work, we investigate a particular class of carbon nanocones, which we name graphannulenes, and present a generalized Hückel rule (GHR) that predicts the character of their ground state based on simply the three topological indices that uniquely define them. Importantly, this rule applies to both flat and curved systems, encompassing a wide variety of known structures that do not satisfy the "classic" 4<i>n</i> + 2 rule such as coronene, corannulene, and Kekulene. We test this rule at the ...[more]

PMID: 34734525

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Toward a Generalized Huckel Rule: The Electronic Structure of Carbon Nanocones.

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Toward a Generalized Hückel Rule: The Electronic Structure of Carbon Nanocones.

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