scholarly journals On the stability of neon cluster ions – Evidence for isomeric structures

2021 ◽  
Vol 462 ◽  
pp. 116528
Author(s):  
Siegfried Kollotzek ◽  
Stefan Bergmeister ◽  
Lukas Tiefenthaler ◽  
Simon Albertini ◽  
Elisabeth Gruber ◽  
...  
Keyword(s):  
Cluster Ions ◽  
The Stability ◽  
Isomeric Structures

STABILITY AND SIZE EFFECT ANALYSIS OF THIN MAGNESIUM NANOWIRES

2010 ◽  
Vol 09 (01n02) ◽  
pp. 47-55
Author(s):  
SANJEEV KUMAR ◽  
PANKAJ SRIVASTAVA
Keyword(s):  
Size Effect ◽  
Hydrogen Adsorption ◽  
Minimum Energy ◽  
Geometrical Structures ◽  
Effect Analysis ◽  
Band Structure Calculations ◽  
Ab Initio Approach ◽  
The Stability ◽  
Isomeric Structures ◽  
Structure Calculations

The stability and size effect analysis of different isomeric structures of Mg n(n = 1–5) nanowires have been investigated by employing ab-initio approach. We have considered various geometrical structures up to five atoms to explore the minimum energy configuration. In the present study, we have calculated various physical properties in large energy interval for all structures. In particular, we have analyzed the effect of shape and size on these calculated values and investigated density of states (DOS) in four different ways to see the microscopic changes in their nature of peaks. We predict that five atom tetrahedral structure is stable having highest binding energy and DOS. The band structure calculations of all wires reflect the possibility of sufficient number of channels for quantum conduction and are metallic in character. In addition, we have also analyzed the effect of hydrogen adsorption on most stabilized geometrical structure of magnesium ( Mg ) nanowire which shows no evidence of better stability in comparison to pure Mg nanowires.

scholarly journals Ion-Size Effects in the Growth Sequences of Metal-Ion-Doped Noble Gas Clusters

1997 ◽  
Vol 17 (2) ◽  
pp. 109-122 ◽  
Author(s):  
Christian Lüder ◽  
Dimitris Prekas ◽  
Michalis Velegrakis
Keyword(s):  
Metal Ion ◽  
Mass Spectra ◽  
Noble Gas ◽  
Magic Number ◽  
Sphere Packing ◽  
Cluster Ions ◽  
Magic Numbers ◽  
Gas Clusters ◽  
The Stability ◽  
Ion Size

We have studied the stability and the structure of doped noble gas cluster ions of the type M+Xn, (M=In, Al, Na, X=Ar, Kr, Xe) by systematically changing the composition M/X and observing changes in the magic number patterns appearing in the mass spectra. When the metal ion radius is comparable to the radius of the noble gas atom, the mass spectra show the familar icosahedral magic numbers n+ 1=13,19,23,26,29,32, 46, 55,... In constrast, for metal ions with radii significantly smaller than the noble gas atoms, we observe a new series of magic numbers n + 9, 11, 17, 21,24, 26,... This series converts into the icosahedral one for larger clusters. Using a simple hard sphere packing model, we show that this new series of magic numbers is consistent with a cluster growth sequence which is based on a capped square antiprism (CSA) geometrical structure of the clusters.

Fragment and cluster ions from gaseous and condensed pyridine produced under electron impact

2018 ◽  
Vol 20 (40) ◽  
pp. 25762-25771 ◽  
Author(s):  
Fabio de A. Ribeiro ◽  
Benedikt Rudek ◽  
Henrique B. A. Cerqueira ◽  
Ricardo R. Oliveira ◽  
Alexandre B. Rocha ◽  
...  
Keyword(s):  
Gas Phase ◽  
Electron Impact ◽  
Cluster Ions ◽  
Ion Distribution ◽  
Carbenium Ion ◽  
The Stability ◽  
And Shifts ◽  
Gas Phase Fragmentation

The ion-distribution from condensed pyridine due to 2 keV electron impact shows hydrogenated fragments and clusters with m/z ≤ 320 u and shifts towards higher masses compared to the gas-phase fragmentation. The formation of a bond between the pyridine and a carbenium ion is crucial for the stability of the selected cluster ions.

Insights into the stability of silicon cluster ions: Reactive etching with O2

2002 ◽  
Vol 117 (7) ◽  
pp. 3219-3223 ◽  
Author(s):  
D. E. Bergeron ◽  
A. W. Castleman
Keyword(s):  
Cluster Ions ◽  
Silicon Cluster ◽  
The Stability

Basicity of the solvent as the main factor determining the stability of iron/sulfido thiolato [Fe4S4(SR)4]- cluster ions in solution

1991 ◽  
Vol 30 (16) ◽  
pp. 3231-3234 ◽  
Author(s):  
H. L. Blonk ◽  
O. Kievit ◽  
E. K. H. Roth ◽  
J. Jordanov ◽  
J. G. M. Van der Linden ◽  
...  
Keyword(s):  
Cluster Ions ◽  
The Stability ◽  
Main Factor

Open discussion

1982 ◽  
Vol 99 ◽  
pp. 605-613
Author(s):  
P. S. Conti
Keyword(s):  
Buenos Aires ◽  
Large Mass ◽  
List Type ◽  
Common Phenomenon ◽  
Open Discussion ◽  
The Stability ◽  
Ring Nebulae

Conti: One of the main conclusions of the Wolf-Rayet symposium in Buenos Aires was that Wolf-Rayet stars are evolutionary products of massive objects. Some questions:–Do hot helium-rich stars, that are not Wolf-Rayet stars, exist?–What about the stability of helium rich stars of large mass? We know a helium rich star of ∼40 MO. Has the stability something to do with the wind?–Ring nebulae and bubbles : this seems to be a much more common phenomenon than we thought of some years age.–What is the origin of the subtypes? This is important to find a possible matching of scenarios to subtypes.

Symmetric Multistep Methods Revisited: II. Numerical Experiments

1999 ◽  
Vol 173 ◽  
pp. 309-314 ◽  
Author(s):  
T. Fukushima
Keyword(s):  
Multistep Methods ◽  
Computational Time ◽  
Integration Time ◽  
Implicit Methods ◽  
Symmetric Methods ◽  
Celestial Bodies ◽  
The Stability ◽  
Predictor Corrector ◽  
Symmetric Multistep Methods ◽  
Integration Errors

AbstractBy using the stability condition and general formulas developed by Fukushima (1998 = Paper I) we discovered that, just as in the case of the explicit symmetric multistep methods (Quinlan and Tremaine, 1990), when integrating orbital motions of celestial bodies, the implicit symmetric multistep methods used in the predictor-corrector manner lead to integration errors in position which grow linearly with the integration time if the stepsizes adopted are sufficiently small and if the number of corrections is sufficiently large, say two or three. We confirmed also that the symmetric methods (explicit or implicit) would produce the stepsize-dependent instabilities/resonances, which was discovered by A. Toomre in 1991 and confirmed by G.D. Quinlan for some high order explicit methods. Although the implicit methods require twice or more computational time for the same stepsize than the explicit symmetric ones do, they seem to be preferable since they reduce these undesirable features significantly.

Uniformity of Magnification from Different Electron Microscopes

1967 ◽  
Vol 25 ◽  
pp. 32-33
Author(s):  
Godfrey C. Hoskins ◽  
V. Williams ◽  
V. Allison
Keyword(s):  
Diffraction Grating ◽  
The Other ◽  
Carbon Replica ◽  
Electron Microscopes ◽  
The Stability

The method demonstrated is an adaptation of a proven procedure for accurately determining the magnification of light photomicrographs. Because of the stability of modern electrical lenses, the method is shown to be directly applicable for providing precise reproducibility of magnification in various models of electron microscopes.A readily recognizable area of a carbon replica of a crossed-line diffraction grating is used as a standard. The same area of the standard was photographed in Phillips EM 200, Hitachi HU-11B2, and RCA EMU 3F electron microscopes at taps representative of the range of magnification of each. Negatives from one microscope were selected as guides and printed at convenient magnifications; then negatives from each of the other microscopes were projected to register with these prints. By deferring measurement to the print rather than comparing negatives, correspondence of magnification of the specimen in the three microscopes could be brought to within 2%.

Sign in / Sign up

Export Citation Format

Share Document