Chemical compounds formed from diacetylene and rare-gas atoms: HKrC4H and HXeC4H.
Chemical compounds formed from diacetylene and rare-gas atoms: HKrC4H and HXeC4H.
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DOI：
10.1021/ja038610x
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发表时间：
2003-12
影响因子：
15
通讯作者：
Hanna Tanskanen;L. Khriachtchev;J. Lundell;Harri Kiljunen;M. Räsänen
中科院分区：
文献类型：
--
作者：
Hanna Tanskanen;L. Khriachtchev;J. Lundell;Harri Kiljunen;M. Räsänen
新的有机稀有气体化合物 HRgC4H（Rg = Kr 或 Xe）在从头计算支持的基质分离实验中得到鉴定。这些化合物是已知稀有气体氢化物中分子最大的。它们是在低温稀有气体基质中通过丁二炔的紫外光解以及随后分别在约 30 K 和 45 K 下对 Kr 和 Xe 进行 H 原子热迁移而制备的。 HRgC4H分子的最强红外吸收带是H-Rg拉伸，其中HKrC4H的1290 cm(-1)和HXeC4H的1532 cm(-1)处的最强分量，并且还发现许多较弱的吸收（C-H拉伸、C-C-C弯曲和C-C-H弯曲模式）与理论预测一致。作为可能最重要的结果，红外吸收光谱表明与最近鉴定的相应 HRgC2H 物质相比，HRgC4H 分子具有一定的进一步稳定性（Khriachtchev 等人 J. Am. Chem. Soc. 2003, 125, 4696 和 Khriachtchev 等人 J. Am. Chem. Soc. 2003, 125, 6876）。计算能量结果支持了这一趋势。预计 HXeC4H 的能量比 H + Xe + C4H 低 2.5 eV，比 HXeC2H 的相应值大约 1 eV。我们预计较大的分子 HRgC6H 和 HRgC8H 更加稳定，并且 HRgC2nH 物种是块状有机稀有气体材料的良好候选者。
New organic rare-gas compounds, HRgC4H (Rg = Kr or Xe), are identified in matrix-isolation experiments supported by ab initio calculations. These compounds are the largest molecules among the known rare-gas hydrides. They are prepared in low-temperature rare-gas matrixes via UV photolysis of diacetylene and subsequent thermal mobilization of H atoms at approximately 30 and 45 K for Kr and Xe, respectively. The strongest IR absorption bands of the HRgC4H molecules are the H-Rg stretches with the most intense components at 1290 cm(-1) for HKrC4H and at 1532 cm(-1) for HXeC4H, and a number of weaker absorptions (C-H stretching, C-C-C bending, and C-C-H bending modes) are also found in agreement with the theoretical predictions. As probably the most important result, the IR absorption spectra indicate some further stabilization of the HRgC4H molecules as compared with the corresponding HRgC2H species identified recently (Khriachtchev et al. J. Am. Chem. Soc. 2003, 125, 4696 and Khriachtchev et al. J. Am. Chem. Soc. 2003, 125, 6876). The computational energetic results support this trend. HXeC4H is predicted to be 2.5 eV lower in energy than H + Xe + C4H, which is approximately 1 eV larger than the corresponding value for HXeC2H. We expect that the larger molecules HRgC6H and HRgC8H are even more stable and the HRgC2nH species are good candidates for bulk organic rare-gas material.