Lumo vs homo5/3/2023 In this sense, strategies to provide thermodynamic or kinetic stabilization are commonly used. 11 The challenge is to shield the highly reactive apical carbons at the five-membered ring (R group in Fig. 6,7 The narrow HOMO–LUMO gap makes this molecule and their derivatives attractive for organic electronic devices 3,8–10 and complementary to acenes. 1 This fact is explained by the existence of a central proaromatic p-quinodimethane ( p-QDM) unit that presents a canonical diradical contribution ( Fig. In contrast to the latter, IF displays high electron affinity due to the presence of the cyclopentadiene rings, thus narrowing the HOMO–LUMO energy gap. Introduction Indenofluorene 1–6 (IF, 1) is considered the formally antiaromatic analogue of pentacene. First principles transport calculations support this high conductance value. Conductance values one order of magnitude higher than those of a reference linear 3-ring para-phenylene ethylene have been found, despite the longer length of the S-to-S molecular junction. Moreover, we have investigated the single-molecule conductance of the antiaromatic indenofluorene for the first time by including thiomethyl (-SMe) anchor groups on the phenylacetylene moiety. Experimental and theoretical data show an increase in the diradical character ( y) and a decrease of the singlet-triplet energy gap. 4-Substituted-2,6-dimethylphenyl acetylene groups placed in the apical carbon of the five-membered rings lead to redshifted absorption maxima ( λ max ranging from 600–700 nm) and considerable narrowing of the HOMO–LUMO energy gap (down to 1.5 eV). E-mail: b Departamento de Química Física Aplicada, Universidad Autónoma de Madrid, 28049 Madrid, Spain c Centro de Instrumentación Científica, Universidad de Granada, 18071 Granada, Spain d Departamento de Química Orgánica e Inorgánica, Facultad de Ciencia y Tecnología, Universidad del País Vasco, 48940, Leioa, Spain e Fundación IMDEA Nanociencia, 28049, Madrid, Spain f Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049, Madrid, Spain g Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040, Madrid, Spain h Condensed Matter Physics Center (IFIMAC), 28049, Madrid, SpainĪ direct, efficient and versatile strategy for the modulation of optoelectronic and magnetic properties of indenofluorene has been developed. * a a Departamento de Química Orgánica, Facultad de Ciencias, Unidad de Excelencia de Química Aplicada a Biomedicina y Medioambiente (UEQ), Universidad de Granada, 18071 Granada, Spain. C, 2022, 10, 11775-11782 Engineering the HOMO–LUMO gap of indenofluorene † ‡
0 Comments
Leave a Reply. |