Organic Mixed Valence Systems. II. Two-Centers and Three-Centers Compounds with Meta Connections around a Central Phenylene Ring

and, Jacques Bonvoisin; Launay, Jean‐Pierre; Verbouwe, Wouter; Auweraer, Mark Van der; Schryver, F. C. De

doi:10.1021/jp9610933

Cited by 88 publications

(70 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[36][37]50 Indeed, these absorptions fall into the spectral range in which intervalence absorptions of bis(triarylamine) radical cations are commonly observed. 16,20,[34][35][51][52][53][54][55][56][57][58][59][60][61] An important difference to the intervalence absorptions of coordination compounds 40,[62][63][64][65] are the comparatively large extinction coefficients of these bands, but this is a (favorable) peculiarity of organic mixed-valence compounds which has been noted many times before. Table 2.…”

Section: -49mentioning

confidence: 99%

Charge Delocalization in a Homologous Series of α,α′-Bis(dianisylamino)-Substituted Thiophene Monocations

et al. 2012

View full text Add to dashboard Cite

A homologous series of three molecules containing thiophene, bithiophene and terthiophene bridges between two redox-active tertiary amino-groups was synthesized and explored. Charge-delocalization in the one-electron oxidized forms of these molecules was investigated by a combination of cyclic voltammetry, near-infrared optical absorption spectroscopy, and EPR spectroscopy. All three cation radicals can be described as organic mixed-valence species, and for all of them the experimental data is consistent with strong delocalization of the unpaired electron. Depending on what model is used for 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 2 analysis of the optical absorption data, estimates for the electronic coupling matrix element (H AB ) range from ∼5000 cm -1 to ∼7000 cm -1 for the shortest member of the homologous series. According to optical absorption and EPR spectroscopy even the terthiophene radical appears to belong either to Robin-Day class III or to a category of radicals commonly denominated as borderline class II / class III systems. The finding of such a large extent of charge delocalization over up to three adjacent thiophene units is remarkable.

show abstract

Section: -49mentioning

confidence: 99%

Charge Delocalization in a Homologous Series of α,α′-Bis(dianisylamino)-Substituted Thiophene Monocations

et al. 2012

View full text Add to dashboard Cite

show abstract

“…[274] [52,275] . Angewandte Aufsätze C. Lambert und A. Heckmann konstanten ausgewertet, die wiederum aus den Reduktionspotentialen berechnet wurden.…”

Section: Organische Mv-verbindungen Mit Bor-redoxzentrenunclassified

Organische gemischtvalente Verbindungen: ein Spielplatz für Elektronen und Löcher

2011

View full text Add to dashboard Cite

Gemischtvalente (MV) Verbindungen sind ausgezeichnete Modellsysteme, um grundlegende Elektronentransport(ET)‐ und Ladungstransfer(CT)‐Phänomene zu untersuchen. Diese sind in komplexen biophysikalischen Prozessen wie der Photosynthese, aber auch in artifiziellen elektronischen Bauteilen von großer Bedeutung. So sind organische MV‐Verbindungen effiziente Lochtransportmaterialien in organischen lichtemittierenden Dioden (OLEDs), Solarzellen und photochromen Fenstern. Die Bedeutung der organischen gemischtvalenten Chemie sollte jedoch weniger in ihrer direkten Anwendbarkeit gesehen werden, als vielmehr in dem riesigen Kenntnisschatz über Elektronentransferphänomene, der durch ihr Studium gewonnen wurde. Die große Vielfalt an organischen Redoxzentren und Brückeneinheiten, die zu MV‐Verbindungen kombiniert werden können, sowie die stete Weiterentwicklung von ET‐Theorien und ET‐Untersuchungsmethoden förderten das enorme Interesse an organischen MV‐Verbindungen in den letzten Jahrzehnten und zeigen das große Potential dieser Verbindungsklasse auf. Das Ziel dieses Aufsatzes ist es, das letzte Jahrzehnt der organischen gemischtvalenten Chemie zusammenzufassen und ihren Einfluss auf moderne funktionelle Materialien hervorzuheben.

show abstract

“…[4] Dendritic triarylamines or 1,3,5-(trisaryl)benzenes have been intensively studied in recent years due to their multi-redox properties. [5,6] In addition, aiming at controlled charge transport, redox-gradient or redox-cascade systems have been pursued by incorporating several kinds of triarylamine units into their oligomeric and dendritic architecture. [7,8] In contrast to the typical holetransport materials with a linearly p-extended system, these moieties as spin-carrying units were isolated in the molecule to avoid the formation of closed-shell electronic structures.…”

Section: Introductionmentioning

confidence: 99%

Structural Changes in 2‐Diarylthiophene‐Substituted Starburst Compounds upon Charging: A Theoretical and Spectroelectrochemical Study

et al. 2008

View full text Add to dashboard Cite

The role of charging in structural changes of 2-diarylaminothiophene-substituted starburst compounds is clarified by combining theoretical and spectroelectrochemical studies. A systematic and comparative theoretical calculation based on density functional theory and semiempirical Austin Model 1 (AM1) calculations is performed on the neutral and charged states of four model tris(5-diarylamino-5-thienyl)-terminated starburst compounds with a central triphenylamine and 1,3,5-triphenylbenzene moiety. Our results indicate that the charging of molecules leads to structural changes by quinoid-type components mostly on the dendrimers terminated by phenothiazinyl fragments. Based on the optimal geometries, the spectroscopic properties were calculated using the semiempirical Zerner's intermediate neglect overlap method. The presented theoretical results and the spin electron distributions of charged states and their spectra are supported by the spectroelectrochemical observations caused by the different electron localization within the studied molecules after charging. The satisfactory agreement between theoretical electronic transitions and experimental values indicates that a rational design of tunable molecular layers in organic devices based on the starburst compounds described is possible.

show abstract

Organic Mixed Valence Systems. II. Two-Centers and Three-Centers Compounds with Meta Connections around a Central Phenylene Ring

Cited by 88 publications

References 7 publications

Charge Delocalization in a Homologous Series of α,α′-Bis(dianisylamino)-Substituted Thiophene Monocations

Charge Delocalization in a Homologous Series of α,α′-Bis(dianisylamino)-Substituted Thiophene Monocations

Organische gemischtvalente Verbindungen: ein Spielplatz für Elektronen und Löcher

Structural Changes in 2‐Diarylthiophene‐Substituted Starburst Compounds upon Charging: A Theoretical and Spectroelectrochemical Study

Contact Info

Product

Resources

About