The synthesis, characterization, and reactivity of nonagermanide, (germanium(9))(n-) (n = 4, 3, 2) Zintl anionic clusters

In this age of communication, the future of microelectronics is held in check. If current miniaturization trends continue to push the semiconductor market towards the manufacture of smaller and more efficient components, device features will soon approach the atomic cluster size, where properties often differ significantly from those of the bulk. Unfortunately, at present, the fundamental structure-property relationships and reactivity of small main-group semiconductor clusters is poorly understood. This is due, in large part, to the lack of clear structural and mechanistic relationships in any kinetically controlled cluster assembly from small molecular clusters to their bulk counterparts. Promise may reside in one unique family of ‘naked’ metal cluster ions, known as Zintl ions, which have been isolated and characterized from solution. In particular, the nine-atom E9 homopolyatomic anionic clusters of Group 14 have been a controversial subject for several decades and remain intensely investigated. The captivating charm and allure of these simple anionic semiconductor species is further realized after an unbiased global theoretical search for ground state larger cluster aggregates of Si_n and Ge _n (9 < n < 26) proposed the tricapped trigonal prism (TTP) E ₉ as the basic building unit.; This research explores, in depth, the synthesis, characterization and reactivity of three fundamentally important nonagermanide anionic semiconductor clusters: Ge₉4−, Ge₉3− , Ge₉2−. Further investigations reveal a remarkable oxidative dimerization process that affords isolated Ge ₁₈6− clusters as well as novel, unprecedented one-dimensional polymers of vertex-linked nido-Ge₉2− cluster anions in _∞1[Ge₉] 2−.