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Revisiting the Intriguing Electronic Features of the BeOBeC Carbyne and Some Isomers: A Quantum-Chemical Assessment.

ABSTRACT: Extensive high-level quantum chemical calculations reveal that the rod-shaped molecule BeOBeC, which was recently generated in matrix experiments, features two nearly isoenergetic 5? quintet (56) and 3? triplet (36) states. Their IR features are hardly distinguishable at finite temperature. The major difference concerns the mode of spin coupling between the terminal beryllium and carbon atoms. Further, the ground-state potential-energy surface of the [2Be,C,O] system at 4K is presented and differences between the photochemical and thermal behaviors are highlighted. Finally, a previously not considered, so far unknown C2v-symmetric rhombus-like four-membered ring 3[Be(O)(C)Be] (35) is predicted to represent the global minimum on the potential-energy surface.

SUBMITTER: Li J

PROVIDER: S-EPMC7540417 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Revisiting the Intriguing Electronic Features of the BeOBeC Carbyne and Some Isomers: A Quantum-Chemical Assessment.

Li Jilai J Geng Caiyun C Weiske Thomas T Zhou Mingfei M Li Jun J Schwarz Helmut H

Angewandte Chemie (International ed. in English) 20200728 39

Extensive high-level quantum-chemical calculations reveal that the rod-shaped molecule BeOBeC, which was recently generated in matrix experiments, exists in two nearly isoenergetic states, the 5 Σ quintet (5 6) and the 3 Σ triplet (3 6). Their IR features are hardly distinguishable at finite temperature. The major difference concerns the mode of spin coupling between the terminal beryllium and carbon atoms. Further, the ground-state potential-energy su ...[more]

PMID: 32568419

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