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Optical gap and fundamental gap of oligoynes and carbyne.

ABSTRACT: The optoelectronic properties of various carbon allotropes and nanomaterials have been well established, while the purely sp-hybridized carbyne remains synthetically inaccessible. Its properties have therefore frequently been extrapolated from those of defined oligomers. Most analyses have, however, focused on the main optical transitions in UV-Vis spectroscopy, neglecting the frequently observed weaker optical bands at significantly lower energies. Here, we report a systematic photophysical analysis as well as computations on two homologous series of oligoynes that allow us to elucidate the nature of these weaker transitions and the intrinsic photophysical properties of oligoynes. Based on these results, we reassess the estimates for both the optical and fundamental gap of carbyne to below 1.6 eV, significantly lower than previously suggested by experimental studies of oligoynes.

SUBMITTER: Zirzlmeier J

PROVIDER: S-EPMC7511338 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Optical gap and fundamental gap of oligoynes and carbyne.

Zirzlmeier Johannes J Schrettl Stephen S Brauer Jan C JC Contal Emmanuel E Vannay Laurent L Brémond Éric É Jahnke Eike E Guldi Dirk M DM Corminboeuf Clémence C Tykwinski Rik R RR Frauenrath Holger H

Nature communications 20200923 1

The optoelectronic properties of various carbon allotropes and nanomaterials have been well established, while the purely sp-hybridized carbyne remains synthetically inaccessible. Its properties have therefore frequently been extrapolated from those of defined oligomers. Most analyses have, however, focused on the main optical transitions in UV-Vis spectroscopy, neglecting the frequently observed weaker optical bands at significantly lower energies. Here, we report a systematic photophysical ana ...[more]

PMID: 32968057

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