"風"の形状のステリルエンドキャプテッドベンゾ[2,1-b:3,4-b']ディチオフェンは,有機薄膜トランジスタにおける高い電気性能を有する
Yahia Didane1, Georg H Mehl, Atsufumi Kumagai
1Ingenierie Moleculaire et Materiaux Fonctionnels, Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), CNRS UPR 3118, Campus Luminy, Aix Marseille Universite, Marseille, France.
Journal of the American Chemical Society
|December 26, 2008
まとめ
ディスティリル-ビチオフェンを橋渡しすることで,空気の有機薄膜トランジスタ (OTFT) の性能を意外に向上させる曲線半導体が生成されます. この新しいカイトの形状の分子は,その平面の対称を大幅に上回ります.
科学分野:
- オーガニック・エレクトロニクス
- マテリアルサイエンス 材料科学
- 半導体物理学の物理
背景:
- 結合された有機半導体は,電子機器にとって極めて重要です.
- 分子設計は半導体の性能に大きく影響する.
- 有機半導体における曲線分子構造はあまり研究されていない.
研究 の 目的:
- ブリッジングディスティリルビチオフェンの電子特性への影響を調査する.
- 有機薄膜トランジスタ (OTFT) で生成された曲線半導体の性能を調査する.
- 性能を平面アナログと比較するために.
主な方法:
- ブリッジされたディスティリル-ビチオフェン誘導体の合成.
- 新しい半導体を使用した有機薄膜トランジスタ (OTFT) の製造と特徴付け.
- 充電キャリアの移動性とスイッチング比率を含む環境条件での性能評価.
主要な成果:
- ディスティリル-ビチオフェンを橋渡しすることで,の形をした,曲がった結合システムが生まれた.
- 曲線半導体は,空気中での優れたOTFT性能を示した.
- 0.1cm2/V.sの移動性 (μ) とオン/オフ比 (>106) を達成しました.
- 性能は,ブリッジのない平面アナログの約5倍でした.
結論:
- 結合システムにおける分子曲線は,OTFT性能に有益である可能性があります.
- の形状のディスティリルビチオフェン誘導体は,空気安定電子機器のための有望な新しい半導体を表しています.
- この作品は,そのような曲線が望ましくないという認識に異議を唱え,その可能性を強調しています.
関連する概念動画
01:26Thermal and Photochemical Electrocyclic Reactions: Overview
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
01:17Thermal Electrocyclic Reactions: Stereochemistry
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
01:13Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Bromination and chlorination of aromatic rings by electrophilic aromatic substitution reactions are easily achieved, but fluorination and iodination are difficult to achieve. Fluorine is so reactive that its reaction with benzene is difficult to control, resulting in poor yields of monofluoroaromatic products. To address this, Selectfluor reagent is used as a fluorine source in which a fluorine atom is bonded to a positively charged nitrogen.
01:18Aromatic Hydrocarbon Cations: Structural Overview
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
Removing one hydrogen from the intervening CH2 group with both...
01:26Photochemical Electrocyclic Reactions: Stereochemistry
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
01:28Stability of Conjugated Dienes
Introduction
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.