biostudies-literatureMiklik DMEXT | Japan Society for the Promotion of ScienceMEXT | Japan Society for the Promotion of Science (JSPS)MEXT | National Institute for Materials Science29https://www.ebi.ac.uk/biostudies/studies/S-EPMC9814942biostudies-literatureUnknown4(1)Acenes and azaacenes lie at the core of molecular materials' applications due to their important optical and electronic features. A critical aspect is provided by their heteroatom multiplicity, which can strongly affect their properties. Here we report pyrazinacenes containing the dihydro-decaazapentacene and dihydro-octaazatetracene chromophores and compare their properties/functions as a model case at an oxidizing metal substrate. We find a distinguished, oxidation-state-dependent conformational adaptation and self-assembly behaviour and discuss the analogies and differences of planar benzo-substituted decaazapentacene and octaazatetracene forms. Our broad experimental and theoretical study reveals that decaazapentacene is stable against oxidation but unstable against reduction, which isCommunications chemistryPyrazinacenes exhibit on-surface oxidation-state-dependent conformational and self-assembly behaviours.PMC9814942JP15K13684Miklik DSvec PBuresova ZLabuta JAriga KMorari CBures FRichards GJKarr PAMiddleton AWakayama YHill JPAhsan AD'Souza FBuimaga-Iarinca LJung TAMori TFatemeh Mousavi SMatsushita YfalsePyrazinacenes exhibit on-surface oxidation-state-dependent conformational and self-assembly behaviours.Acenes and azaacenes lie at the core of molecular materials' applications due to their important optical and electronic features. A critical aspect is provided by their heteroatom multiplicity, which can strongly affect their properties. Here we report pyrazinacenes containing the dihydro-decaazapentacene and dihydro-octaazatetracene chromophores and compare their properties/functions as a model case at an oxidizing metal substrate. We find a distinguished, oxidation-state-dependent conformational adaptation and self-assembly behaviour and discuss the analogies and differences of planar benzo-substituted decaazapentacene and octaazatetracene forms. Our broad experimental and theoretical study reveals that decaazapentacene is stable against oxidation but unstable against reduction, which is2021-01-01T00:00:00Z2021 Mar2025-04-29T10:47:48.94Z2025-04-06T19:41:29.531ZS-EPMC98149423669755310.1038/s42004-021-00470-w