Comparison of intensities between doubly charged ions [M+2H]2+ and singly charged ions [M+H]+ of gramicidin S by electrospray mass spectrometry

1991 ◽  
Vol 5 (8) ◽  
pp. 349-353 ◽  
Author(s):  
Minoru Sakairi ◽  
Alfred L. Yergey
Keyword(s):  
Mass Spectrometry ◽  
Electrospray Mass Spectrometry ◽  
Doubly Charged Ions ◽  
Gramicidin S ◽  
Singly Charged ◽  
Doubly Charged ◽  
Charged Ions

Oxide, Hydroxide, and Doubly Charged Analyte Species in Inductively Coupled Plasma/Mass Spectrometry

1986 ◽  
Vol 40 (4) ◽  
pp. 434-445 ◽  
Author(s):  
M. A. Vaughan ◽  
G. Horlick
Keyword(s):  
Mass Spectrometry ◽  
Inductively Coupled Plasma ◽  
Inductively Coupled ◽  
Doubly Charged Ions ◽  
Oxide Hydroxide ◽  
Plasma Mass Spectrometry ◽  
Singly Charged ◽  
Doubly Charged ◽  
Oxide Ions ◽  
Charged Ions

In inductively coupled plasma/mass spectrometry analyte, M may be distributed among several species forms including doubly charged ions (M2+), singly charged ions (M+), mono-oxide ions (MO+), and hydroxide ions (MOH+). Detailed data are presented for Ba to illustrate the dependence of the ion count of these species and their ratios (M2+/M+, MO+/M+, and MOH+/M+) on nebulizer flow rate, plasma power, and sampling depth. Although these data are representative of most elements, many form oxides to a much greater degree than Ba; data are presented for Ti, W, and Ce to illustrate this fact. These various analyte species are important in that serious interelement interferences can occur because of spectral overlap. An extensive pair of tables indicating potential spectral interferences caused by element oxide, hydroxide, and doubly charged ions is presented.

Doubly-charged ions in desorption mass spectrometry

1983 ◽  
Vol 55 (8) ◽  
pp. 1310-1313 ◽  
Author(s):  
David N. Heller ◽  
James. Yergey ◽  
Robert J. Cotter
Keyword(s):  
Mass Spectrometry ◽  
Desorption Mass Spectrometry ◽  
Doubly Charged Ions ◽  
Doubly Charged ◽  
Charged Ions

A collisionally activated dissociation (CAD) and computational investigation of doubly and singly charged DMSO complexes of Cu2+

2005 ◽  
Vol 83 (11) ◽  
pp. 1921-1935 ◽  
Author(s):  
John A Stone ◽  
Timothy Su ◽  
Dragic Vukomanovic
Keyword(s):  
Electron Transfer ◽  
Collision Energy ◽  
Nbo Analysis ◽  
Computational Investigation ◽  
Doubly Charged Ions ◽  
Collisionally Activated Dissociation ◽  
The Difference ◽  
Singly Charged ◽  
Doubly Charged ◽  
Charged Ions

The singly and doubly charged Cu(II)–DMSO complexes formed by electrospray have been examined by CAD and computation. The CAD spectra were obtained as a function of collision energy. The doubly charged ions, [Cu(DMSO)n]2+, were observed only for n ≥ 2. For n = 3, dissociation leads mainly to [Cu(DMSO)2]+ + DMSO+, with only a trace of [Cu(DMSO)2]2+. Although [Cu(DMSO)]2+ was never detected, computation shows that the n = 1 complex exists in a potential well. Loss of DMSO+ is computed to be exothermic for n = 1–3, the exothermicity decreasing as n increases. The singly charged complexes in the ESI spectra were [CuX(DMSO)n]+ (X = Cl, Br, NO3, HSO4, n = 1 or 2). The CAD spectra showed competition between electron transfer from anion to metal followed by loss of X and loss of DMSO+. Experiment and computation show that for [CuX(DMSO)]+, loss of X is the preferred decomposition at low collision energy. NBO analysis shows that electron transfer to Cu from DMSO decreases in [Cu(DMSO)n]2+ as n increases, the bonding becoming more electrostatic and less covalent. In [CuX(DMSO)n]+, the negative charge on X is much less than unity with most of the difference appearing on the DMSO ligand(s).Key words: copper–DMSO complexes, electrospray, CAD, structures.

Can direct field-evaporation of doubly charged ions and post-ionisation from the singly charged state co-exist?

2007 ◽  
Vol 39 (2-3) ◽  
pp. 128-131 ◽  
Author(s):  
Th. Ganetsos ◽  
A. W. R. Mair ◽  
G. L. R. Mair ◽  
L. Bischoff ◽  
Ch. Akhmadaliev ◽  
...  
Keyword(s):  
Field Evaporation ◽  
Charged State ◽  
Doubly Charged Ions ◽  
Singly Charged ◽  
Doubly Charged ◽  
Charged Ions

Evidence from SIMS of Doubly-Charged Boron Contamination During Singly Charged-Ion Implantation

1990 ◽  
Vol 48 (2) ◽  
pp. 316-317
Author(s):  
D. S. Simons ◽  
P. H. Chi ◽  
D. B. Novotny
Keyword(s):  
Ion Implantation ◽  
Main Peak ◽  
Charged State ◽  
Exchange Reactions ◽  
Doubly Charged Ions ◽  
Multiply Charged ◽  
Residual Gas ◽  
Singly Charged ◽  
Doubly Charged ◽  
Charged Ions

When a dopant is introduced into a semiconductor material by ion implantation, it is sometimes desirable to accelerate and implant the ion in a multiply-charged state. This has the effect of increasing the energy and range of the ion without increasing the accelerating potential. Most modern ion implanters are of the pre-analysis type. In this design the ions are first accelerated through a modest extraction potential, e.g., 25 keV. This is followed by deflection for mass-to-charge selection in an analyzer magnet, after which the selected ions undergo final acceleration. Charge-exchange reactions between the doubly-charged ions and residual gas have been found to occur between the analyzing magnet and the final acceleration section. These reactions produce singly-charged ions that receive only half of the energy of the doubly-charged ions during final acceleration. For the case of B++ implantation the resulting implant profile shows a shallow-depth shoulder due to B+, the amplitude of which may be greater than 50% of the main peak.

Charge stripping and delayed autoionization in doubly charged ions of the noble gases

1985 ◽  
Vol 402 (1823) ◽  
pp. 373-400 ◽  
Keyword(s):  
Black Body ◽  
Black Body Radiation ◽  
Translational Energy ◽  
Rare Gases ◽  
Doubly Charged Ions ◽  
Free Process ◽  
Singly Charged ◽  
Double Focusing ◽  
Doubly Charged ◽  
Charged Ions

Doubly charged ions of each of the rare gases neon, argon, krypton and xenon, formed by electron impact and accelerated through 6 kV in a double-focusing mass spectrometer, are ionized to the corresponding triply charged ions via processes of at least two general kinds. The first proceeds under collision-free conditions, and can be attributed to delayed (microsecond) autoionization. An alternative explanation involving transitions from high Rydberg states, induced by the 350 K black-body radiation within the analyser vacuum housing, cannot be entirely ruled out. Other ionization processes require a collision with a molecule of collision gas, and result in a measurable loss of translational energy. In this paper the knowledge of analogous processes of the corresponding singly charged ions is reviewed, the general features of the translational energy spectra are established, and effort is devoted to the characterization of the collision-free process. The collision-induced processes have been interpreted in terms of known metastable states of the doubly charged ions.

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