Au (((CN) (((2) ((-) の有意な共性結合の証拠がある
Xue-Bin Wang1, Yi-Lei Wang, Jie Yang
1Department of Physics, Washington State University, 2710 University Drive, Richland, Washington 99354, USA.
Journal of the American Chemical Society
|October 29, 2009
まとめ
この研究では,黄金ダイシアン化物イオン (Au(CN) 2−) 内における黄金-炭素結合における有意な共振結合が明らかになりました. 実験的および計算的方法は,この共性特性を確認し,化合物の驚くべき安定性を説明します.
科学分野:
- 無機化学 無機化学とは
- 物理化学 物理化学
- コンピューティング・ケミストリー
背景:
- 金二シアン化物イオン (Au(CN) 2−) は,非常に安定した金化合物である.
- その安定性にもかかわらず,その化学結合の正確な性質,特にAu-C結合は,まだ完全に理解されていません.
研究 の 目的:
- Au(CN) 2-.のAu-C結合における共振結合特性に関する直接的な実験的証拠を提供すること.
- 電子構造とAu (CN) 2の化学結合を,光譜分析と計算分析によって解明する.
- Au(CN) 2-の結合を,そのより軽い同種であるAg(CN) 2-とCu(CN) 2-と比較するには.
主な方法:
- 118nmの分離光子を用いた光電子スペクトロスコーピー.
- シルバーディシアン化物 (Ag(CN) 2−) と銅ディシアン化物 (Cu(CN) 2−) との実験比較.
- 密度関数理論 (DFT) と高レベルの初期計算.
主要な成果:
- Au-Cのストレッチモードでの振動の進行の観察は,Au ((CN) 2-.ですべての脱離の移行に対して行われます.
- Cu(CN) 2−の観察された原子のような移行と対照的に,Au(CN) 2−における共振結合を強調する.
- 詳細な電子構造情報は,Au(CN) 2-. . . のために取得されました.
結論:
- 直接的な実験的証拠は,Au ((CN) 2-. .のAu-C結合における有意な共性特性を確認しています.
- 相対論的効果は,Au(CN) 2-.で観察された強い共振結合において重要な役割を果たします.
- 特定された共振結合は,黄金ダイシアン化物イオンの例外的な安定性を説明する.
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