Single ionization

Wannier G H 1953 The threshold law for single Ionization of atoms or Ions by eleotrons Phys. Rev. 90 817-25... 

II, second spectra from singly ionized atoms, and so on for successive stages of ionization. 

Association reaction (associative combination). The reaction of a (slow moving) ion with a neutral species, wherein the reactants combine to form a single ionized species. 

In its simplest form, a mass spectrometer is an instmment that measures the mass-to-charge ratios ml of ions formed when a sample is ionized by one of a number of different ionization methods (1). If some of the sample molecules are singly ionized and reach the ion detector without fragmenting, then the ml ratio of these ions gives a direct measurement of the molecular weight. The first instmment for positive ray analysis was built by Thompson (2) in 1913 to show the existence of isotopic forms of the stable elements. Later, mass spectrometers were used for precision measurements of ionic mass and abundances (3,4). 

This is a transient discrete electric discharge which takes place between two conductors which are at different potentials, bridging the gap in the form of a single ionization channel (Plate 4). Based on light emission measurements of sparks with symmetrical electrode geometry, the energy is dissipated approximately uniformly along the channel. This is in contrast with asym-... 

Fig. 8. Mass spectrum, with background subtracted, of pbo-toionized (Cfto) Rbv clusters containing both singly and doubly ionized species tbe solid line connects peaks belonging to groups of singly ionized clusters with a fixed value of n. Note tbe dominant peaks corresponding to (C (,Rb, ) Rb and (QoRb,.,) Rb2 (marked...

Fig. 9. Mass spectra of singly (top) and doubly (bottom) ionized Cf2)Li,. clusters note tbe prominent features at x = 7 for singly ionized and x = 8 for doubly ionized clusters and at X = 12 in both spectra.

A bell-shaped pH-rate profile can also be produced in a two-step reaction involving a single ionizable group if the rate-determining step changes when the pH is altered. An example, the oximation of acetone, is shown in Fig. 5-12. 

Table 1. Positions of a few levels with respect to the double and single ionized ground states.

The atomic spectrum of singly ionized helium He+ with i = 4, 2 = 5, 6,. .. is known as the Pickering series. Calculate the energy differences, wave numbers, and wavelengths for the first three lines in this spectrum and for the series limit. 

Merkle, R., Savin, A., Preuss, H., 1992, Singly Ionized First-Row Dimers and Hydrides Calculated With the Fully Numerical Density Program NUMOL , J. Chem. Phys., 97, 9216. 

This formalism was originally devised for single ionization of ground-state atoms, but has now been successfully applied to the calculation of electron impact ionization cross sections for a range of molecules, radicals, clusters, and excited state atoms. Like many of the semiempirical and semiclassical methods used to describe the electron impact process, the theory has its roots in work carried out by J.J. Thomson, who used classical mechanics to derive an expression for the atomic electron impact ionization cross section,2... 

Ionization is the process of removing one or more electrons from a neutral atom. This results in the loss of units of negative charge by the affected atom. The atom becomes electrically positive (a positive ion). The products of a single ionizing event are called an electron-ion pair. 

An electron-ion pair is the product of a single ionizing event. 

In the past few years there has been a very intense effort to understand the process of single ionization in ion-atom collisions. Experiments in this area have followed largely along three main paths recoil-ion momentum spectroscopy... 

We begin Section II with a theoretical description of the CDW and CDW-EIS theory to describe the single ionization of helium, neon, argon, and molecular hydrogen targets. 

In Section III we discuss the applicability of these models for kinematically complete experiments on target single ionization in ion-atom collisions, which have been performed using the technique of recoil-ion momentum spectroscopy. The examples illustrated will include the pioneering experiments [2,4,5] of... 

More details of the emission of ultralow- and low-energy electrons from fast heavy ion-atom collisions may be seen in the doubly differential cross sections as functions of the longitudinal electron velocity for increasing transverse electron velocity. Examples considered in this chapter include singly ionizing... 

Figure 1. Calculated longitudinal momentum distributions for the ejected electron in single ionization of He by 3.6-MeV/amu Ni24+ ions. Experimental data are from Moshammer et al. [2], Theoretical results CDW results [20], CDW-EIS1 results [20], CDW-EIS2 results [48].

Figure 7. Longitudinal momentum distributions of the emitted electron, the recoiling target ion, and the projectile after the single ionization of helium by 3.6-MeV/amu Au53+ ions. Experimental data are from Schmitt et al. [50]. Also shown are CDW-EIS calculations [50] and CTMC calculations [50].

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