Department of Chemistry and Biochemistry, National Chung Cheng University, Chia-Yi, Taiwan.
Phys Chem Chem Phys. 2013 Jun 28;15(24):9701-9. doi: 10.1039/c3cp50447f. Epub 2013 May 14.
We have computationally predicted a new class of stable noble-gas molecules FNgBNR (Ng = Ar, Kr, Xe; R = H, CH3, CCH, CHCH2, F, and OH). The FNgBNR were found to have compact structures with F-Ng bond lengths of 1.9-2.2 Å and Ng-B bond lengths of ~1.8 Å. The endoergic three-body dissociation energies of FNgBNH to F + Ng + BNH were calculated to be 12.8, 31.7, and 63.9 kcal mol(-1), for Ng = Ar, Kr, and Xe, respectively at the CCSD(T)/CBS level. The energy barriers of the exoergic two-body dissociation to Ng + FBNH were calculated to be 16.1, 24.0, and 33.2 kcal mol(-1) for Ng = Ar, Kr, and Xe, respectively. Our results showed that the dissociation energetics is relatively insensitive to the identities of the terminal R groups. The current study suggested that a wide variety of noble-gas containing molecules with different types of R groups can be thermally stable at low temperature, and the number of potentially stable noble-gas containing molecules would thus increase very significantly. It is expected some of the FNgBNR molecules could be identified in future experiments under cryogenic conditions in noble-gas matrices or in the gas phase.
我们通过计算预测了一类新的稳定的稀有气体分子 FNgBNR（Ng=Ar、Kr、Xe；R=H、CH3、CCH、CHCH2、F 和 OH）。研究发现，FNgBNR 具有紧凑的结构，F-Ng 键长为 1.9-2.2 Å，Ng-B 键长约为 1.8 Å。在 CCSD(T)/CBS 水平下，我们计算得到 Ng=Ar、Kr 和 Xe 时，FNgBNH 分解为 F+Ng+B-NH 的三原子离解能分别为 12.8、31.7 和 63.9 kcal/mol。Ng+FBNH 分解为 Ng+FBN 的两原子离解能垒分别为 16.1、24.0 和 33.2 kcal/mol。结果表明，离解能对终端 R 基团的性质相对不敏感。本研究表明，低温下，具有不同类型 R 基团的各种稀有气体分子都可能具有热稳定性，潜在的稳定稀有气体分子数量将显著增加。预计在未来的稀有气体基质或气相低温实验中，可以识别出一些 FNgBNR 分子。
