Ubiquitous 8 and 29 kDa gold: Alkanethiolate cluster compounds: Mass-spectrometric determination of molecular formulas and structural implications
Ubiquitous 8 and 29 kDa gold: Alkanethiolate cluster compounds: Mass-spectrometric determination of molecular formulas and structural implications
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DOI：
10.1021/ja8005379
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发表时间：
2008-07-09
影响因子：
15
通讯作者：
Tsukuda, Tatsuya
中科院分区：
文献类型：
--
作者：
Chaki, Nirmalya K.;Negishi, Yuichi;Tsukuda, Tatsuya
使用电喷雾电离质谱法评估了迄今为止普遍存在的核心质量为 8 和 29 kDa 的烷硫醇保护的金簇的分子式和电荷态分布。 8 和 29 kDa 簇被确定为分别由单一物质 [Au-38(SCn)(24)](z) 和 [Au-144(SCn)(59)](z) 组成，电荷态 z >= 0。根据最近通过实验确定的相关系统的结构，讨论了 Au-38(SCn)(24) 和 Au-144(SCn)(59) 可能的几何结构理论上：[Au-25(SR)(18)](-) 和 Au-102(SR)(44)，其中 Au 核受到单体 [-SR-Au-SR-] 和/或二聚体 [-SR-Au-SR-Au-SR-] 的保护。由于几何因素，它们的优先形成和化学稳健性被认为与高稳定性相关，而无论底层的金核如何，金-硫醇盐界面都呈现出共同的图案。
The molecular formulas and charge state distributions of thus-far known ubiquitous alkanethiolate-protected gold clusters with core-masses of 8 and 29 kDa were assessed using electrospray ionization mass spectrometry. The 8 and 29 kDa clusters were determined to be composed of single species, [Au-38(SCn)(24)](z) and [Au-144(SCn)(59)](z), respectively, with charge states of z >= 0. Possible geometric structures for Au-38(SCn)(24) and Au-144(SCn)(59) are discussed, based on the structures of relevant systems that have been recently determined experimentally and theoretically: [Au-25(SR)(18)](-) and Au-102(SR)(44), in which the Au cores are protected by monomers [-SR-Au-SR-] and/or dimers [-SR-Au-SR-Au-SR-]. Their preferential formation and chemical robustness are proposed as being associated with high stability due to geometric factors, while the Au-thiolate interface takes on common motifs regardless of the underlying Au core.