Spontaneous Symmetry Breaking in Cyclo[18]Carbon

Autor(es)

Pereira, Zenner S. ^[1] ; da Silva, Edison Z. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Rural Semiarido UFERSA, Dept Ciencia & Tecnol, BR-59780000 Caraubas, RN - Brazil

^[2] Univ Estadual Campinas, Inst Phys Gleb Wataghin, CP 6165, BR-13083985 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Physical Chemistry A; v. 124, n. 6, SI, p. 1152-1157, FEB 13 2020.
• Citações Web of Science: 0

Resumo

After the experimental evidence of polyynic as the stable form of cyclo{[}18]carbon, in the present paper, using ab initio electronic structure calculations, we show that this result is a symmetry breaking event, a consequence of the second-order Jahn-Teller effect. We show that the eigenfunctions associated with lowest unoccupied molecular orbitals (LUMO) and LUMO + 1, the excited states of this ring molecule, interact with the eigenfunctions associated with the ground state (occupied states), and this interaction stabilizes the less symmetric polyynic form of cyclo{[}18] carbon with D-9h symmetry, instead of the cumulenic form. The frontier state interactions are responsible for the distortions in the symmetry in the electronic structures, lowering the energy and making the polyynic form the stable one with alternating triple and single bonds. (AU)

• Processo FAPESP: 16/23891-6 - Modelagem computacional da matéria condensada
• Beneficiário: Alex Antonelli
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs