title: Optical Properties and Charge-Transfer Excitations in Edge-Functionalized All-Graphene Nanojunctions.
abstract: We investigate the optical properties of edge-functionalized graphene nanosystems, focusing on the formation of junctions and charge-transfer excitons. We consider a class of graphene structures that combine the main electronic features of graphene with the wide tunability of large polycyclic aromatic hydrocarbons. By investigating prototypical ribbon-like systems, we show that, upon convenient choice of functional groups, low-energy excitations with remarkable charge-transfer character and large oscillator strength are obtained. These properties can be further modulated through an appropriate width variation, thus spanning a wide range in the low-energy region of the UV-vis spectra. Our results are relevant in view of designing all-graphene optoelectronic nanodevices, which take advantage of the versatility of molecular functionalization, together with the stability and the electronic properties of graphene nanostructures.
authors: †Centro S3, CNR-Istituto Nanoscienze, I-41125 Modena, Italy.|‡Dipartimento di Fisica, Università di Modena e Reggio Emilia, I-41125 Modena, Italy.
authors: Caterina
authors: C
authors: Cocchi
authors: †Centro S3, CNR-Istituto Nanoscienze, I-41125 Modena, Italy.
authors: Deborah
authors: D
authors: Prezzi
authors: †Centro S3, CNR-Istituto Nanoscienze, I-41125 Modena, Italy.|‡Dipartimento di Fisica, Università di Modena e Reggio Emilia, I-41125 Modena, Italy.
authors: Alice
authors: A
authors: Ruini
authors: ¶Instituto de Física, Universidade de São Paulo, 05508-900 São Paulo, SP, Brazil.
authors: Marilia J
authors: MJ
authors: Caldas
authors: †Centro S3, CNR-Istituto Nanoscienze, I-41125 Modena, Italy.|‡Dipartimento di Fisica, Università di Modena e Reggio Emilia, I-41125 Modena, Italy.
authors: Elisa
authors: E
authors: Molinari
keywords: UV−vis spectrum; ZINDO; carbon nanostructures; configuration interaction; exciton