锗分族元素二元团簇及其与Co形成的团簇离子

The Binary Anion Clusters of Ge/Sn, Ge/Pb, Sn/Pb, Co/Ge, Co/Sn and Co/Pb

通过比较激光烧蚀E1/E2(代表Ge/Sn,Ge/Pb和Sn/Pb)和Co/E(E为Ge、Sn、Pb)混合样品形成的二元团簇负离子飞行时间质谱分布和谱峰的相对强度及形成的幻数团簇离子峰,发现E1/E2二元团簇离子中原子量大的锗分族元素在团簇离子中占主要组分,而原子量小的元素则少量掺杂,其组成和分布特点说明其结构和性质与纯E团簇离子相似,可能的结构为该类负离子团簇所有原子都在笼结构的骨架上;对于二元团簇离子GeSn9-、GePb9-和SnPb9-其结构可能是双帽反四棱柱构型,只是每个原子均为骨架的一部分.而对激光烧蚀过渡金属钴与锗分族元素的混合物的研究发现,反应形成了丰富的Co/E二元合金团簇负离子,分析发现该类簇离子为钴内包覆于E(锗分族元素)笼状结构.幻数离子CoGe10-、CoSn10-和CoPb10-可能具有双帽四角反棱柱结构,而CoPb12-可能具有二十面体构型,钴原子均为笼状结构的中心.

The binary cluster anions of Ge/Sn, Ge/Pb, Sn/Pb, Co/Ge, Co/Sn and Co/Pb binary cluster ions, produced by direct laser ablation, were studied with a Tandem TOF mass spectrometer. The experiments show that E-1/E-2. (E-1/E-2 denotes Ge/Sn, Ge/Pb and Sn/Pb) binary clusters dominantly distribute in the lower mass region, in which the number of heavy atom is much larger than that of light atom. And composition and distribution of these binary clusters indicate that their structures and properties are similar to those pure group-14 elements cluster. By laser ablating the mixtures of transition metal cobalt and group-14 elements, mass spectra showed that abundance Co/E(E denotes Ge, Sn and Pb) cluster formed in higher mass range. Magic number CoGel(10)(-), CoSn10- and CoPb10- may have bi-capped tetragonal antiprism structure and CoPb12- is icosahedral structure. The difference between E-1/E-2 and Co/E binary cluster anions shows that all atoms for E-1/E-2 binary cluster anions are on the framework of the cage, while the cobalt atom for Co/E binary cluster is inside the cage of E.