水素結合 (NH4+/NH2NH3+) による超分子カチオン組を [Ni(dmit) ] 基の分子導体および磁石に (NH4+/NH2NH3+) 冠エーテル) とする
Tomoyuki Akutagawa1, Tatsuo Hasegawa, Takayoshi Nakamura
1Research Institute for Electronic Science, Hokkaido University, Sapporo 060-0812, Japan. takuta@imd.es.hokudai.ac.jp
Journal of the American Chemical Society
|July 26, 2002
まとめ
この研究では,電気を伝導するニッケル・ビス・ディチオール・エーテル (Ni) ([Ni (dmit) ]) 2) 塩に組み込まれたクラウンエーテルを含むアンモニア (NH4+) とヒドラジニウム (NH2-NH3+) を用いて,新しい水素結合の超分子カチオン組を調査しています. これらのアセンブリは,ユニークな構造と半導体特性を持ち,そのうちの1つが鉄磁気相互作用を示しています.
科学分野:
- 超分子化学 超分子化学
- 材料科学 材料科学とは
- 固体化学 固体化学
背景:
- 電子伝導性金属ディチオレン複合体,例えばニッケルビスディチオレン ([Ni(dmit) [2]) は,その多様な電子特性で知られている.
- 超分子組成は,水素結合のような非共性相互作用を通じて調節可能な構造と機能を提供します.
- クラウンエーサーは,様々なカチオンと複合体を形成し,結晶の詰め込みと性質に影響を与える能力のある多用途のマクロサイクルです.
研究 の 目的:
- 異なるクラウンエーテルを持つアンモニア (NH4+) とヒドラジニウム (NH2-NH3+) の新しい水素結合の超分子カチオン組を合成し,特徴づけること ([12]crown-4, [15]crown-5, [18]crown-6).
- これらのアセンブリを電気伝導性[Ni(dmit) 2塩に組み込み,その構造的および電子的性質を調査する.
- 結晶構造と導電性に起因するカチオン・クラウン・エーテル相互作用の影響を調査する.
主な方法:
- アンモニア/ヒドラジニウムとクラウンエーテルを含む超分子カチオン組成の合成.
- これらのアセンブリを[Ni(dmit) 2塩に組み込む.
- 単結晶X線 difraktionで結晶構造と超分子配列を決定する.
- 半導体特性を評価するための電気伝導度測定.
- アセンブリ内の水素結合相互作用 (N-H··O) の分析.
主要な成果:
- 非ステイキオメトリックカチオン占有率と静的障害を示すアンモニア・クラウン・エーテル・アセンブリによるピラミッド形およびイオンチャネル構造の形成により,局所的伝導電子が生じる.
- サンドイッチとクラブサンドイッチの構造を持つ固体ヒドラジニウム・クラウン・エーテル・アセンブリを初めて特定した.
- (NH2-NH3+) 2 ((([15]crown-5) 3 (Ni (((dmit)) 2) での鉄磁気相互作用 (ワイス温度 = +1 K) の検出6.
- (NH2-NH3+) 0.8 (([18]crown-6) [Ni (((dmit) 2) 2) と (NH4+) 0.76 (([18]crown-6) [Ni (((dmit) 2) 2) 2の結晶間のイソモルフィズムで, [18]crown-6.crown-6の構造的適応性を示しています.
結論:
- クラウンエーテルを伴うアンモニアとヒドラジニウムの水素結合超分子カチオン組は, [Ni (((dmit)) 2塩に効果的に組み込まれ,多様な結晶構造を生成します.
- クラウンエーサーのサイズと柔軟性,およびカチオン-クラウンエーサーの相互作用は,結果として得られる材料の包装,ステキオメトリー,および電子特性に大きく影響します.
- これらの新しいアセンブリは,調節可能な電子および磁気特性を有する新しい機能的材料を開発するための有望なプラットフォームを表しています.
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