Abstract In order to obtain fundamental insight into the bonding properties of transition metals, the ( v ′ ,0) B-X transitions ( v ′ = 0 - 2 ) of the heteronuclear CuAg dimer are re-investigated by applying non-linear four-wave mixing and laser-induced fluorescence spectroscopy. The CuAg molecules in a molecular beam are produced by laser ablation of a Cu/Ag alloy target. Rotationally resolved spectra of the B-X transition are recorded. The measurements yield accurate molecular constants for four isotopologues and an equilibrium distance r e = 2.4577 ± 0.0003 A for the B state. In particular, the B state is identified as an Ω = 0 + ion-pair state. The results corroborate the important contribution of the charge-transfer state to the metal–metal bond. The results are in good agreement with the recent calculations at the MRCI level of theory (Alizadeh et al., 2014).

中文翻译：

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CuAg B0+态的离子对特性

摘要 为了从根本上了解过渡金属的键合性质，通过应用非线性四波混合重新研究了异核 CuAg 二聚体的 ( v ' ,0) BX 跃迁 ( v ' = 0 - 2 )和激光诱导荧光光谱。分子束中的 CuAg 分子是由 Cu/Ag 合金靶材的激光烧蚀产生的。记录 BX 跃迁的旋转分辨光谱。测量产生四种同位素体的准确分子常数，平衡距离 re = 2.4577 ± 0.0003 A 对于 B 状态。特别地，B 状态被识别为 Ω = 0 + 离子对状态。结果证实了电荷转移状态对金属-金属键的重要贡献。