C7クラスター:構造と赤外線周波数
J R Heath1, R A Sheeks, A L Cooksy
1Department of Chemistry, University of California, Berkeley 94720, USA.
Science (New York, N.Y.)
|August 24, 1990
まとめ
研究者はC7炭素群を観察し,特徴づけ,その線形構造と振動特性を決定しました. この発見は,この炭素群の潜在的天体物理学的検出に役立ちます.
科学分野:
- 物理化学 物理化学
- スペクトロスコーピーは,スペクトロスコーピーを用います.
- アストロケミストリー アストロケミストリー
背景:
- 炭素クラスターは,恒星間化学と物質科学において極めて重要です.
- C7のような小さな炭素群の性質を理解することは,天体物理学モデリングに不可欠です.
- 以前のC7の特徴は限られていたため,さらなる調査が必要であった.
研究 の 目的:
- C7炭素群を観察し,特徴づけること.
- C7.の分子構造と振動周波数を決定する.
- C7の天体物理学的検出を容易にするデータを提供する.
主な方法:
- 炭素のクラスターを生成するために,グラファイトのレーザー蒸発.
- クラスター形成のためのアルゴンジェットにおける超音速膨張.
- ダイオードレーザーの吸収スペクトロスコーピーで,ゲート検出により,ロビビレーション線を検出します.
主要な成果:
- C7.の4つの反対称なストレッチファンダメンタルに36のロビブラーションラインが観測されました.
- スペクトルは,C7が対称な線形分子であることを確認した.
- 効果的平均ボンド長が1.2736(4) アングストロムであった.
- 振動周波数が2138.1951 (((10) 互換センチメートルで測定されました.
結論:
- C7の実験結果は,ab initio計算とよく一致しています.
- 特徴付けはC7の重要なスペクトロスコピクデータを提供しています.
- この研究は,C7を天体物理環境で特定する見込みを高めます.
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