scholarly journals Evolution of the charge localization process in xenon cluster ions: From tetramer to dimer cores as a function of cluster size

2002 ◽  
Vol 116 (17) ◽  
pp. 7558-7563 ◽  
Author(s):  
T. Laarmann ◽  
A. Kanaev ◽  
K. von Haeften ◽  
H. Wabnitz ◽  
R. von Pietrowski ◽  
...  
Keyword(s):  
Cluster Size ◽  
Cluster Ions ◽  
Charge Localization ◽  
Xenon Cluster

RECOMBINATION OF OPPOSITELY CHARGED AQUEOUS CLUSTER IONS USING ELECTROSTATICALLY MERGED ION BEAMS

1996 ◽  
Vol 03 (01) ◽  
pp. 655-660 ◽  
Author(s):  
B. PLASTRIDGE ◽  
K.A. COWEN ◽  
D.A. WOOD ◽  
M.H. COHEN ◽  
J.V. COE
Keyword(s):  
Rate Constants ◽  
Cluster Size ◽  
Collision Energy ◽  
Relative Rate ◽  
Center Of Mass ◽  
Cluster Ions ◽  
Charged Cluster ◽  
Relative Rate Constants ◽  
Oppositely Charged ◽  
Electrostatic Quadrupole

A new method for studying cluster-cluster interactions is introduced which involves merging mass-selected beams of oppositely charged cluster ions with an electrostatic quadrupole deflector. Recombination is monitored by measuring the rate of fast neutral production. Relative rate constants have been measured for the reaction of H 3O+( H 2 O )n+ OH −( H 2 O )m as a function of cluster size (m=n=0–3), which display a pronounced enhancement with clustering. Relative rate constants have also been measured as a function of center-of-mass collision energy for a heavily clustered reaction (n=3, m=3) and a lightly clustered reaction (n=1, m=0) revealing that clustering produces a dramatic change in the reaction mechanism.

Production and Characterization of Deposited Mono-Sized Clusters

1990 ◽  
Vol 206 ◽  
Author(s):  
Donald M. Cox ◽  
Barbara Kessler ◽  
Pierre Fayet ◽  
Wolfgang Eberhardt ◽  
Rex D. Sherwood ◽  
...  
Keyword(s):  
Cluster Size ◽  
Surface Coverage ◽  
Metal Clusters ◽  
High Energy ◽  
Cluster Ions ◽  
Rare Gas ◽  
Ion Sputtering ◽  
Transition Metal Clusters ◽  
X Ray

ABSTRACTUsing high energy rare gas ion sputtering of metal targets, we are able to produce nanoamps of mass selected transition metal clusters. Mono-sized cluster ions are deposited at low kinetic energy upon substrates, e.g. silica or carbon, and are then characterized using UV and x-ray photoemission. In this paper we will discuss photoemission measurements of the 4f7/2 core level energies of Au (1–5,7 atom samples) clusters deposited on silica. From such studies we are beginning to understand how electronic structure, cluster stability and mobility depend on (deposited) cluster size, surface coverage, and substrate temperature.

Molecular Dynamics Simulations of Cluster-size Effect on Sputtering Process with Reactive Gas Cluster Ions

2005 ◽  
Vol 908 ◽  
Author(s):  
Takaaki Aoki ◽  
Jiro Matsuo
Keyword(s):  
Molecular Dynamics ◽  
Size Effect ◽  
Cluster Size ◽  
Incident Energy ◽  
Md Simulations ◽  
Cluster Ions ◽  
Experimental Conditions ◽  
Near Surface ◽  
The Impact ◽  
Reactive Cluster

AbstractTo investigate the size-effect of reactive clusters on sputtering processes, we performed molecular dynamics (MD) simulations of reactive cluster ions with various sizes impacting on solid targets. Various sizes of fluorine clusters, (F2)30, (F2)300 and (F2)3000, were irradiated on a Si(100) target at the same total incident energy of 6 keV. These clusters were irradiated on the same target one after another in order to reproduce real experimental conditions such as the accumulation of fluorine atoms in the target. The MD simulations of sequential cluster impacts enabled to perform various statistical analyses regarding the sputtered particles. The study of cluster size distributions showed that the sputtering process by reactive cluster ion impact has similarity with the emission from quasi-liquid materials excited to hyper-thermal conditions by ion bombardment. However, the major sputtered particles were different with each other; Si for (F2)30 (100 eV/atom), SiF2 for (F2)300 (10 eV/atom), and SiF3 for (F2)3000 (1 eV/atom). At the impact of a large size cluster with low incident energy, a large number of Si-F bondings were generated at the cluster-target interface surface, which enhances formation of volatile SiFx compounds with many fluorine atoms. In contrast, a small cluster with high kinetic energy-per-atom could cause the formation of numerous energetic surface atoms at the near surface region, which could be sputtered without being well fluoridated.

Irradiation Effects of Ar-Cluster Ion Beams on Si Surfaces

1993 ◽  
Vol 316 ◽  
Author(s):  
G. H. Takaoka ◽  
G. Sugahara ◽  
R. E. Hummel ◽  
J. A. Northby ◽  
M. Sosnowski ◽  
...  
Keyword(s):  
Cluster Size ◽  
Ion Beams ◽  
Cluster Ions ◽  
Irradiation Effects ◽  
Damage Layer ◽  
Ion Energies ◽  
Cluster Ion Beams ◽  
Cluster Ion ◽  
The Mean

ABSTRACTThe effects of energetic Ar cluster ion impacts on Si(111) surfaces have been studied for cluster energies up to l5keV. The mean cluster size was about 1000 atoms, and the smaller sizes could be systematically excluded. Si samples irradiated at different cluster ion energies were analyzed by RBS, ellipsometry, and differential reflectometry. Implantation of Ar in samples irradiated with cluster ions was found by RBS to be detectable, but very small in comparison with samples irradiated with monomer ions of the same energy. The thickness of the damage layer as measured by both ellipsometry and differential reflectometry was also much smaller in the cluster ion irradiated samples.

COLLISIONAL PROCESSES INVOLVING SIZE-SELECTED SODIUM-CLUSTER IONS

1996 ◽  
Vol 03 (01) ◽  
pp. 679-682 ◽  
Author(s):  
H. TANAKA ◽  
T. MIZUNO ◽  
J. HIROKAWA ◽  
S. NONOSE ◽  
T. KONDOW
Keyword(s):  
Cross Section ◽  
Cluster Size ◽  
Collision Energy ◽  
Branching Fractions ◽  
Pair Interaction ◽  
Cluster Ions ◽  
Absolute Cross Section ◽  
Tandem Mass ◽  
Ion Guide ◽  
Ion Production

Collision-induced reactions of [Formula: see text](n=2–9) with Ne and Kr were investigated by means of a Tandem mass spectrometer equipped with octapole ion guide. The dominant processes were evaporation of a Na atom from [Formula: see text] with even sizes or Na 2 molecules from those with odd sizes. The absolute cross section for the reaction was measured as functions of the parent-cluster size and the collision energy. The branching fractions of the daughter-ion production were also determined. These results are interpreted in a scheme of a pair interaction in jellium background.

scholarly journals Noble gas cluster ions

2018 ◽  
Vol 174 ◽  
pp. 06003
Author(s):  
Yunus Kaya ◽  
Yalçin Kalkan ◽  
Rob Veenhof
Keyword(s):  
Density Functional ◽  
Noble Gas ◽  
Kinetic Studies ◽  
Basis Set ◽  
Cluster Ions ◽  
Functional Theory ◽  
B3lyp Method ◽  
Xenon Cluster ◽  
The Density Functional Theory ◽  
Potential Basis

In this work, a reaction mechanism of formation of noble gas (Ng) cluster ions has been theoretically investigated in detail. The kinetic studies of formation of Xe+Xe cluster in Xe, Ar+Ar cluster ions in Ar, and Ne+Ne cluster ions in Ne have been made as theoretically. The optimized structures in the ground state were calculated using the density functional theory (DFT) by the B3LYP method combined with the Stuttgart/Dresden effective core potential basis set (SDD). In addition, we calculated the rate constants of all cluster formations. The results are 1.15 × 10−31, 3.58 × 10−31, 0.23 × 10−31cm6/s, respectively for Neon, Argon, Xenon cluster ions.

MOLECULAR-DYNAMICS SIMULATION OF SURFACE SPUTTERING BY ENERGETIC RARE-GAS CLUSTER IMPACT

1996 ◽  
Vol 03 (01) ◽  
pp. 1023-1027 ◽  
Author(s):  
Z. INSEPOV ◽  
I. YAMADA
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Cluster Size ◽  
Silicon Surfaces ◽  
Dynamics Simulation ◽  
Cluster Ions ◽  
Rare Gas ◽  
Cluster Energy ◽  
Small Clusters ◽  
Surface Sputtering

The molecular-dynamics simulation is used for simulation of sputtering of gold and silicon surfaces by accelerated [Formula: see text] cluster ions with n~55–200 and energies of 10–100 eV per cluster atom. The sputtering yield Y can be described by a power dependency Y ∝E2.35 on the total cluster energy. The result of the calculation agrees with the experimental data point at the energy of 29 keV and cluster size of 300 Ar atoms. The simulation shows that the sputtered flux has a significant lateral-momentum component and the sputtered surface materials contain not only atoms but also small clusters.

scholarly journals Magnetotransport Properties of Ferromagnetic Nanoparticles in a Semiconductor Matrix Studied by Precise Size-Selective Cluster Ion Beam Deposition

Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2192
Author(s):  
Nicolas Gack ◽  
Gleb Iankevich ◽  
Cahit Benel ◽  
Robert Kruk ◽  
Di Wang ◽  
...  
Keyword(s):  
Coulomb Blockade ◽  
Cluster Size ◽  
Magnetic Semiconductors ◽  
Average Distance ◽  
Ion Beam ◽  
Cluster Ions ◽  
Tunneling Magnetoresistance ◽  
Material System ◽  
Ge Matrix ◽  
Dependent Transport

The combination of magnetic and semiconducting properties in one material system has great potential for integration of emerging spintronics with conventional semiconductor technology. One standard route for the synthesis of magnetic semiconductors is doping of semiconductors with magnetic atoms. In many semiconductor–magnetic–dopant systems, the magnetic atoms form precipitates within the semiconducting matrix. An alternative and controlled way to realize such nanocomposite materials is the assembly by co-deposition of size-selected cluster ions and a semiconductor. Here we follow the latter approach to demonstrate that this fabrication route can be used to independently study the influence of cluster concentration and cluster size on magneto-transport properties. In this case we study Fe clusters composed of approximately 500 or 1000 atoms soft-landed into a thermally evaporated amorphous Ge matrix. The analysis of field and temperature dependent transport shows that tunneling processes affected by Coulomb blockade dominate at low temperatures. The nanocomposites show saturating tunneling magnetoresistance, additionally superimposed by at least one other effect not saturating upon the maximum applied field of 6 T. The nanocomposites’ resistivity and the observed tunneling magnetoresistance depend exponentially on the average distance between cluster surfaces. On the contrary, there is no notable influence of the cluster size on the tunneling magnetoresistance.

Threshold Energy for Generating Damage with Cluster Ion Irradiation

2002 ◽  
Vol 749 ◽  
Author(s):  
Toshio Seki ◽  
Takaaki Aoki ◽  
Atsuko Nakai ◽  
Jiro Matsuo ◽  
Gikan H. Takaoka
Keyword(s):  
Cluster Size ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Irradiation ◽  
Threshold Energy ◽  
Cluster Ions ◽  
Si Substrates ◽  
Large Size ◽  
Mean Size ◽  
Cluster Ion ◽  
The Mean

ABSTRACTIn order to understand the damage formation by cluster ion irradiation, Si substrates were irradiated with Ar cluster ions at the acceleration energy of 1–20keV. The mean size of cluster was about 3000 atoms. The amount of damage after Ar cluster ion irradiation was measured with Rutherford backscattering spectrometry (RBS). The amount of damage was decreased with decrease of the energy and no damage formed at less than 2keV. This energy of 2keV represents the threshold energy to generate damage with the cluster size of 3000. According to Molecular dynamics (MD) simulation, the damage formation with cluster ion irradiation also depends on cluster size. The size dependence of amount of damage has been investigated experimentally. The cluster size distribution could be changed with the ionization condition and could be measured using Time-of-Flight (TOF) method. The threshold energy was increased with cluster size. These results indicate that undamaged films can be created by using large size of cluster ion with low acceleration energy.

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