Ligated Aluminum Cluster anions, LAln− (n = 1-14, L = N[Si(Me)3]2)

A wide range of low oxidation state aluminum-containing cluster anions, LAln− (n = 1-14, L = N[Si(Me)3]2), were produced via reactions between aluminum cluster anions and hexamethyldisilazane (HMDS). These clusters...

Exploring the water adsorption and reactivity in series of doped aluminum cluster anions

We present a systematic density functional study of central- and surface-doped aluminum cluster anions Al12X- (X=Mg, B, Ga, Si, P, Sc-Zn), their interactions and reactivity with water. Adsorption of water...

Mass separated particle flux from a laser-ablation metal cluster source

Flux waveforms of aluminum cluster beams supplied from a laser-ablation cluster source were precisely investigated under various source conditions such as background pressure, ablation laser intensity, and nozzle structure. A time-of-flight mass spectroscopy revealed that aluminum clusters with sizes up to 200 were generated and the amount of the clusters could be maximized by choosing a proper background pressure (~2 MPa) and an ablation laser fluence (~40 mJ/cm2). Flux waveforms of clusters having specific sizes were carefully reconstructed from the observed mass spectra. It is found that the pulse widths of the aluminum cluster beams were typically about 100 µs and much smaller than that of the monoatomic aluminum beam, indicating that the cluster formation was limited in a relatively small volume in the laser-ablated vapor. Introducing a conical nozzle having a large open angle was also found to enhance the cluster beam velocity and reduce its pulse width. A velocity measurement of particles in the cluster beam was conducted to examine the velocity spread of the supplied clusters. We found that the aluminum clusters were continuously released from the source for about 100 µs and this release time mainly determined the pulse width of the cluster beam, suggesting that controlling the behavior of an ablated vapor plume in the waiting room of the cluster source holds the key to drastically improving the cluster beam flux.