Single-Crystal X-ray Structure of the Cation Radical of 3‘,4‘-Dibutyl-2,5‘‘-diphenyl-2,2‘:5‘,2‘‘-terthiophene:  Definitive Evidence for π-Stacked Oxidized Oligothiophenes

Graf, David D.; Campbell, John P.; Miller, Larry L.; Mann, Kent R.

doi:10.1021/ja960194b

Cited by 95 publications

(70 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[18][19][20][21][22][23] In particular, p dimers of oligothiophene radical cations were proposed two decades ago to play a key role in electronic conduction of p-doped polythiophenes. [24] Investigations into the mechanism of the interaction between oligothiophene radical cations [1][2][3][4][5][6][7][8][25][26][27][28][29][30] deepen the understanding of the chemistry of this particularly attractive building block for organic electronics. For instance, it has been found that the tendency for intermolecular p dimerization can be attenuated and, in some cases, shut down when bulky groups are inserted in the b positions at thiophene rings; [31][32][33][34] note the evidence from X-ray crystallography that the closest intermolecular contact in the p dimer of nonhindered systems takes place at the central rings.…”

Section: Introductionmentioning

confidence: 99%

“…For instance, it has been found that the tendency for intermolecular p dimerization can be attenuated and, in some cases, shut down when bulky groups are inserted in the b positions at thiophene rings; [31][32][33][34] note the evidence from X-ray crystallography that the closest intermolecular contact in the p dimer of nonhindered systems takes place at the central rings. [25,26,29] As a result of the attachment of bulky side groups, unfavorable steric interactions may occur, thereby preventing p oligomers from close intermolecular contacts leading to a sizeable p-orbital overlap upon oxidation, an arrangement that is nevertheless highly desirable to achieve a good p-type charge-carrier mobility. [35] However, the steric hindrance of dimerization of cationic p-conjugated oligothiophenes provides valuable information on the intrinsic properties of positively charged p systems in a segregated state and can be considered an important technique for the fabrication of "insulated molecular wires" in molecular devices.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Multistep π Dimerization of Tetrakis(n‐decyl)heptathienoacene Radical Cations: A Combined Experimental and Theoretical Study

Ferrón

Capdevila‐Cortada

Balster

et al. 2014

Chemistry A European J

View full text Add to dashboard Cite

Radical cations of a heptathienoacene α,β-substituted with four n-decyl side groups (D4T7(.) (+) ) form exceptionally stable π-dimer dications already at ambient temperature (Chem. Comm. 2011, 47, 12622). This extraordinary π-dimerization process is investigated here with a focus on the ultimate [D4T7(.) (+) ]2 π-dimer dication and yet-unreported transitory species formed during and after the oxidation. To this end, we use a joint experimental and theoretical approach that combines cyclic voltammetry, in situ spectrochemistry and spectroelectrochemistry, EPR spectroscopy, and DFT calculations. The impact of temperature, thienoacene concentration, and the nature and concentration of counteranions on the π-dimerization process is also investigated in detail. Two different transitory species were detected in the course of the one-electron oxidation: 1) a different transient conformation of the ultimate [D4T7(.) (+) ]2 π-dimer dications, the stability of which is strongly affected by the applied experimental conditions, and 2) intermediate [D4T7]2 (.) (+) π-dimer radical cations formed prior to the fully oxidized [D4T7]2 (.) (+) π-dimer dications. Thus, this comprehensive work demonstrates the formation of peculiar supramolecular species of heptathienoacene radical cations, the stability, nature, and structure of which have been successfully analyzed. We therefore believe that this study leads to a deeper fundamental understanding of the mechanism of dimer formation between conjugated aromatic systems.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Multistep π Dimerization of Tetrakis(n‐decyl)heptathienoacene Radical Cations: A Combined Experimental and Theoretical Study

Ferrón

Capdevila‐Cortada

Balster

et al. 2014

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…Well-ordered and crystalline oligothiophenes are currently being investigated for optoelectronic applications especially in the form of molecular wires [73][74][75][76] using raw as well as alkylsubstituted forms including 16-, 20-, and 27-mers. Besides crystalline oligothiophenes, amorphous oligothiophenes [76,77] have also been used in several devices as reported in published literature [73,75,[78][79][80][81][82][83].…”

Section: Organic Molecules For Device Applicationsmentioning

confidence: 99%

Organic semiconductors for device applications: current trends and future prospects

Ahmad

2014

Journal of Polymer Engineering

View full text Add to dashboard Cite

Abstract:With the rich experience of developing silicon devices over a period of the last six decades, it is easy to assess the suitability of a new material for device applications by examining charge carrier injection, transport, and extraction across a practically realizable architecture; surface passivation; and packaging and reliability issues besides the feasibility of preparing mechanically robust wafer/substrate of single-crystal or polycrystalline/ amorphous thin films. For material preparation, parameters such as purification of constituent materials, crystal growth, and thin-film deposition with minimum defects/ disorders are equally important. Further, it is relevant to know whether conventional semiconductor processes, already known, would be useable directly or would require completely new technologies. Having found a likely candidate after such a screening, it would be necessary to identify a specific area of application against an existing list of materials available with special reference to cost reduction considerations in large-scale production. Various families of organic semiconductors are reviewed here, especially with the objective of using them in niche areas of large-area electronic displays, flexible organic electronics, and organic photovoltaic solar cells. While doing so, it appears feasible to improve mobility and stability by adjusting π-conjugation and modifying the energy bandgap. Higher conductivity nanocomposites, formed by blending with chemically conjugated C-allotropes and metal nanoparticles, open exciting methods of designing flexible contact/interconnects for organic and flexible electronics as can be seen from the discussion included here.

show abstract

“…However, detailed studies on the precise structures of thçse species are rather limited. The X-ray crystal structure of the radical-cation salt of terthiophene end-capped with phenyl groups (36,37) has been reported where the formation of so-called π-dimers was discussed in detail. In the caSe of BCO-annelated oligothiophenes 24, such π-π interaction is inhibited by stearic hindrance, and, as such, their properties are of great significance for investigation of cationic oligothiophenes as single molecules (38).…”

Section: Oligothiophenesmentioning

confidence: 99%

Super-Stabilization of π-Conjugated Cations by Annelation to Bicyclic Frameworks

Komatsu

2007

ACS Symposium Series

View full text Add to dashboard Cite

As exemplified by the synthesis of the extraordinarily stable tropylium ion, the annelation of cyclic π-conjugated cations with rigid σ-framework, bicyclo[2.2.2]octene, has been found to be an effective method for creation of unusually stable cationic π-conjugated systems. By using this method, detailed X-ray crystallographic studies have been conducted for the monomeric radical-cation salts of hydrocarbons such as cyclooctatetraene and a series of benzenoid condensed aromatics and of sulfur containing compounds such as thiophene, dithiins, and oligothiophenes. Some of these species can be further oxidized to dications, and also undergo intriguing rearrangements to cationic species with novel structures. The results are well interpreted by the use of theoretical calculations. 32

show abstract

Single-Crystal X-ray Structure of the Cation Radical of 3‘,4‘-Dibutyl-2,5‘‘-diphenyl-2,2‘:5‘,2‘‘-terthiophene: Definitive Evidence for π-Stacked Oxidized Oligothiophenes

Cited by 95 publications

References 21 publications

Multistep π Dimerization of Tetrakis(n‐decyl)heptathienoacene Radical Cations: A Combined Experimental and Theoretical Study

Multistep π Dimerization of Tetrakis(n‐decyl)heptathienoacene Radical Cations: A Combined Experimental and Theoretical Study

Organic semiconductors for device applications: current trends and future prospects

Super-Stabilization of π-Conjugated Cations by Annelation to Bicyclic Frameworks

Contact Info

Product

Resources

About