In:
Chemistry – A European Journal, Wiley, Vol. 22, No. 23 ( 2016-06), p. 7978-7986
Abstract:
Simple modification of benzo[ h ]benz[5,6] acridino[2,1,9,8‐ klmna ]acridine‐8,16‐dione, an old and almost‐forgotten vat dye, by reduction of its carbonyl groups and subsequent O ‐alkylation, yields solution‐processable, electroactive, conjugated compounds of the periazaacene type, suitable for the use in organic electronics. Their electrochemically determined ionization potential and electron affinity of about 5.2 and −3.2 eV, respectively, are essentially independent of the length of the alkoxyl substituent and in good agreement with DFT calculations. The crystal structure of 8,16‐dioctyloxybenzo[ h ]benz[5,6] acridino[2,1,9,8‐ klmna ]acridine ( FC‐8 ), the most promising compound, was solved. It crystallizes in space group P and forms π‐stacked columns held together in the 3D structure by dispersion forces, mainly between interdigitated alkyl chains. Molecules of FC‐8 have a strong tendency to self‐organize in monolayers deposited on a highly oriented pyrolytic graphite surface, as observed by STM. 8,16‐Dialkoxybenzo[ h ]benz[5,6] acridino[2,1,9,8‐ klmna ]acridines are highly luminescent, and all have photoluminescence quantum yields of about 80 %. They show efficient electroluminescence, and can be used as guest molecules with a 4,4′‐bis( N ‐carbazolyl)‐1,1′‐biphenyl host in guest/host‐type organic light‐emitting diodes. The best fabricated diodes showed a luminance of about 1900 cd m −12 , a luminance efficiency of about 3 cd A −1 , and external quantum efficiencies exceeding 0.9 %.
Type of Medium:
Online Resource
ISSN:
0947-6539
,
1521-3765
DOI:
10.1002/chem.201600513
Language:
English
Publisher:
Wiley
Publication Date:
2016
detail.hit.zdb_id:
1478547-X
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