ヘクサアジドシリケート (IV) イオン:合成,性質,分子構造
Alexander C Filippou1, Peter Portius, Gregor Schnakenburg
1Humboldt-Universität zu Berlin, Institut für Chemie, Brook-Taylor-Strasse 2, 12489 Berlin, Germany. filippou@chemie.hu-berlin.de
Journal of the American Chemical Society
|October 17, 2002
まとめ
研究者らは,新種のシリコン化合物であるbis (((triphenylphosphoranylidene)) アムニウムヘキザジドシリケートを合成し,窒素含有量が高くなった. この安定した塩は高温で分解し,窒素ガスやその他の製品を生成します.
科学分野:
- 無機化学 無機化学とは
- マテリアルサイエンス 材料科学
- 協調化化学について
背景:
- シリコンのアジド複合体は,高い窒素含量と潜在的エネルギー特性により興味を惹きます.
- 以前の研究では,様々なアジドメタラートが調査されていますが,シリコンベースのヘキザジド複合体はあまり一般的ではありません.
研究 の 目的:
- 新しいヘクサジドシリケート塩を合成し,特徴づけること.
- 合成された化合物の熱安定性と分解経路を調査する.
- ヘキザジドシリケートアニオンの構造および電子特性を決定する.
主な方法:
- シリコンテトラクロライドとビス・トライフェニルフォスフォリニリデン・アンモニア・アジドからビス・トライフェニルフォスフォリニリデン・アンモニア・ヘキザジドシリケートの合成.
- 安定性と分解温度を評価するために,熱重力測定分析 (TG-DTA) を含む熱分析.
- 塩の結晶構造を決定するX線結晶学.
- 構造的および電子的分析のためのスペクトロスコピー技術 (IR,ラマン,29Si,14N NMR) と計算方法.
主要な成果:
- ヘキザジドシリケート塩 (PPN) 2[Si(N3) 6の選択的合成を達成しました.
- この化合物は,214°Cで融解し,256°Cと321°Cで分解し,驚くべき熱安定性を示しています.
- 結晶構造は,離散的なPPN+カチオンと,S6対称性および90%の窒素含有量を持つ稀な,八面体[Si(N3) 6) 2-アニオンを示しています.
- 顕微鏡および計算データにより,溶液中のS6対称性を持つ無傷の[Si(N3) 6) 2-アニオンの存在が確認されました.
結論:
- 新しい,高度に窒素性のヘクサジドシリケート塩が,成功裏に合成され,特徴づけられました.
- 化合物は,定義された分解段階を持つ,有意な熱安定性を示しています.
- [Si(N3) 6) 2-アニオンは,希少な八面体SiN6の枠組みを有し,ヘキザジドメタラートに対する窒素含有量の新しい基準を表しています.
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