ビス-1,2,3-チアセレナゾリル二元体における圧力強化伝導性は,
Leanne Beer1, Jaclyn L Brusso, Robert C Haddon
1Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Journal of the American Chemical Society
|December 22, 2005
まとめ
新しいピリジン-ブリッジされたチアセレナゾリウムラジカルは,半導体特性を示す. 外圧は伝導性を大幅に高め,これらの新材料の弱い金属状態への移行を示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- オーガニック・エレクトロニクス
背景:
- 新型ヘテロサイクリック化合物の合成と特徴付けは,新しい電子材料の開発に不可欠です.
- オーガニックラジカルの構造-性質関係を理解することは,高度な半導体設計の鍵です.
研究 の 目的:
- N-アルキル化ピリジン橋渡し1,2,3-チアセレナゾロ-1,2,3-チアセレナゾリウム塩とその相応のラジカルを合成し,特徴づけること.
- これらの急性化合物の電子および磁気特性を調査するために.
- 外部の圧力の導電性に対する影響を調査する.
主な方法:
- シアセレナゾリウムカチオンの化学および電気化学的還元により,根幹種を生成する.
- 単結晶X線微分法で結晶構造を決定する.
- 温度変数磁気,伝導,近赤外線光学測定.
- 線形マフィン・ティン・オービタル (LMTO) バンド構造の計算.
- 適用された水立圧下での導電性測定.
主要な成果:
- N-アルキル化ピリジン橋渡しチアセレナゾリウム塩とその基的形態の合成に成功しました.
- ラジカルの結晶はイソ構造で,ピを積み重ねた配列で,有意な分子間Se- -Se,Se- -S,Se- -Nの接触がある.
- これらの材料は,小帯域ギャップ半導体として,室温伝導率約10−6 S cm−1.1の半導体として動作します.
- 外圧により導電性が劇的に増加し,4GPaで10−1 S cm−1 (R1=Me) と10−2 S cm−1 (R1=Et) に達する.
- 圧力下では,活性化エネルギーは著しく低下し,弱い金属状態への移行を示します.
結論:
- 合成されたピリジン橋渡しチアセレナゾリウムラジカルは,小帯域のギャップ半導体材料として有望である.
- 分子間相互作用は,それらの固体状態の性質において重要な役割を果たします.
- 外圧は,それらの電子伝導性を調節する効果的な手段であり,金属に近い状態につながる.
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