[Nb@Ge ] : New Family Members of Ge-Based Intermetalloid Clusters.

During the past two decades, single-atom-centered medium-sized germanium clusters [M@Ge ] (M=transition metals, n>12) have been extensively explored, both from theoretical perspectives and experimental gas-phase syntheses. However, the actual structural arrangements of the Ge and Ge endohedral cages are still ambiguous and have long remained an unresolved problem for experimental implementation. In this work, we successfully synthesize 13-/14-vertex Ge clusters [Nb@Ge ] (1) and [Nb@Ge ] (2), which are structurally characterized and exhibit unprecedented topologies, neither classical deltahedra nor 3-connected polyhedral structures.

Open Shells in Endohedral Clusters: Structure and Bonding in the [Fe@Ge] Anion and Comparison to Isostructural [Co@Ge].

The anionic cluster [Fe@Ge] has been characterized and shown to be isostructural to the known -symmetric α isomer of the cobalt analogue [Co@Ge]. Together with the known pair of compounds [Co@Ge] and [Fe@Ge], the title compound completes a set of four closely related germanium clusters that allow us to explore how the metal-metal and metal-cage interactions evolve as a function of size and of the identity of the metal. The results of spin-unrestricted density functional theory (DFT) and multiconfigurational self-consistent field (MC-SCF) calculations present a consistent picture of the electronic structure where transfer of electron density from the metal to the cage is significant, particularly in the Fe clusters where the exchange stabilization of unpaired spin density is an important driving force.

A passive wireless hydrogen surface acoustic wave sensor based on Pt-coated ZnO nanorods.

Using a passive wireless sensor to detect hydrogen can reach the goals of reducing cost and increasing the lifetime since the sensor can work without batteries. In this paper, a passive wireless hydrogen SAW sensor operating at room temperature has been achieved by combining a SAW tag and a resistive hydrogen sensor. The SAW tag is fabricated on a 128 degrees YX-LiNbO(3) substrate and its central frequency is 433 MHz.