Di-benzoquinone Cyclopentadithiophene Diradicaloids Show Spin-States Optical Transitions and Anomalous NIR Emission

We have prepared a series of bis(semiquinone) compounds with dithiophene bridges of different length that evolve from closed-shell (smaller compound) to full diradical (longer compound) for which the narrow singlet-triplet energy gap allows the triplet population at 298 K. The medium size system has...

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Detalles Bibliográficos
Autores: Privado Urda, María, Moles , Sergio, Casanova , David, Casado , Juan, Barrejón Araque, Miriam, Cruz Manrique, María Pilar de la, Langa de la Puente, Fernando
Tipo de recurso: artículo
Fecha de publicación:2024
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/40190
Acceso en línea:https://hdl.handle.net/10578/40190
Access Level:acceso abierto
Palabra clave:Diradicaloids
Dithiophene oligomers
Intersystem crossing
Kasha rule
Singlet-triplet gap
Thermal spin-crossover
Descripción
Sumario:We have prepared a series of bis(semiquinone) compounds with dithiophene bridges of different length that evolve from closed-shell (smaller compound) to full diradical (longer compound) for which the narrow singlet-triplet energy gap allows the triplet population at 298 K. The medium size system has a variety of photonic properties with absorptions and emission in the optical near-infrared region mediated by a unique case of anti-Kasha emission. A whole set of optical absorption/emission and vibrational steady state spectroscopies as well as picosecond transient absorption spectroscopy, all complemented with spectroelectrochemistry and theoretical calculations, is presented.