Raston Paul L, Jäger Wolfgang
Department of Chemistry, University of Adelaide, SA 5005, Australia.
Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
J Chem Phys. 2015 Apr 14;142(14):144308. doi: 10.1063/1.4917420.
We report the Fourier transform microwave spectra of the a-type J = 1-0 transitions of the binary and ternary CO-(pH2)2, CO-pH2-He, CO-HD, and CO-(oD2)N=1,2 clusters. In addition to the normal isotopologue of CO for all clusters, we observed the transitions of the minor isotopologues, (13)C(16)O, (12)C(18)O, and (13)C(18)O, for CO-(pH2)2 and CO-pH2-He. All transitions lie within 335 MHz of the experimentally or theoretically predicted values. In comparison to previously reported infrared spectra [Moroni et al., J. Chem. Phys. 122, 094314 (2005)], we are able to tentatively determine the vibrational shift for CO-pH2-He, in addition to its b-type J = 1-0 transition frequency. The a-type frequency of CO-pH2-He is similar to that of CO-He2 [Surin et al., Phys. Rev. Lett. 101, 233401 (2008)], suggesting that the pH2 molecule has a strong localizing effect on the He density. Perturbation theory analysis of CO-oD2 reveals that it is approximately T-shaped, with an anisotropy of the intermolecular potential amounting to ∼9 cm(-1).
我们报告了二元和三元CO-(pH2)2、CO-pH2-He、CO-HD以及CO-(oD2)N=1,2团簇的a型J = 1-0跃迁的傅里叶变换微波光谱。除了所有团簇的CO正常同位素分子外，我们还观测到了CO-(pH2)2和CO-pH2-He的次要同位素分子(13)C(16)O、(12)C(18)O和(13)C(18)O的跃迁。所有跃迁都在实验或理论预测值的335 MHz范围内。与先前报道的红外光谱[Moroni等人，《化学物理杂志》122, 094314 (2005)]相比，除了CO-pH2-He的b型J = 1-0跃迁频率外，我们还能够初步确定其振动位移。CO-pH2-He的a型频率与CO-He2的相似[Surin等人，《物理评论快报》101, 233401 (2008)]，这表明pH2分子对He密度有很强的局域化作用。对CO-oD2的微扰理论分析表明，它近似为T形，分子间势的各向异性约为9 cm(-1)。
