Simple ion

Simple ion source, showing the housing (block) with electron beam for El. 

Metallic Antimonides. Numerous binary compounds of antimony with metallic elements are known. The most important of these are indium antimonide [1312-41 -0] InSb, gallium antimonide [12064-03-8] GaSb, and aluminum antimonide [25152-52-7] AlSb, which find extensive use as semiconductors. The alkali metal antimonides, such as lithium antimonide [12057-30-6] and sodium antimonide [12058-86-5] do not consist of simple ions. Rather, there is appreciable covalent bonding between the alkali metal and the Sb as well as between pairs of Na atoms. These compounds are useful for the preparation of organoantimony compounds, such as trimethylstibine [594-10-5] (CH2)2Sb, by reaction with an organohalogen compound. 

Each type of mass spectrometer has its associated advantages and disadvantages. Quadrupole-based systems offer a fairly simple ion optics design that provides a certain degree of flexibility with respect to instrument configuration. For example, quadrupole mass filters are often found in hybrid systems, that is, coupled with another surface analytical method, such as electron spectroscopy for chemical analysis or scanning Auger spectroscopy. 

The density of simple ions near the water/vapor interface in simulated films of water is reduced relative to the bulk density [74-76]. The depletion... 

Biomolecules interact with one another through molecular surfaces that are structurally complementary. How can various proteins interact with molecules as different as simple ions, hydrophobic lipids, polar but uncharged carbohydrates, and even nucleic acids ... 

In previous chapters we have discussed the chemical and physical properties of many kinds of substances. For the most part, these materials were made up of either small molecules or simple ions. In this chapter, we will be concerned with an important class of compounds containing large molecules. We call these compounds polymers. 

An alternative to the formation of neutral metal chelates for solvent extraction is that in which the species of analytical interest associates with oppositely charged ions to form a neutral extractable species.6 Such complexes may form clusters with increasing concentration which are larger than just simple ion pairs, particularly in organic solvents of low dielectric constant. The following types of ion association complexes may be recognised. 

If the reaction at the indicator electrode involves complex ions, satisfactory polarograms can be obtained only if the dissociation of the complex ion is very rapid as compared with the diffusion rate, so that the concentration of the simple ion is maintained constant at the electrode interface. Consider the general case of the dissociation of a complex ion ... 

Pulsed source techniques have been used to study thermal energy ion-molecule reactions. For most of the proton and H atom transfer reactions studied k thermal) /k 10.5 volts /cm.) is approximately unity in apparent agreement with predictions from the simple ion-induced dipole model. However, the rate constants calculated on this basis are considerably higher than the experimental rate constants indicating reaction channels other than the atom transfer process. Thus, in some cases at least, the relationship of k thermal) to k 10.5 volts/cm.) may be determined by the variation of the relative importance of the atom transfer process with ion energy rather than by the interaction potential between the ion and the neutral. For most of the condensation ion-molecule reactions studied k thermal) is considerably greater than k 10.5 volts/cm.). 

The actions of zinc and aluminium differ. In general, metal ions such as zinc merely serve to neutralize the acid and are present in solution as simple ions (Holroyd Salmon, 1956 O Neill et al., 1982). But aluminium has a special effect in contrast to zinc, it prevents the formation of crystallites during the cement-forming reaction in zinc phosphate cements. 

The liquid is an aqueous solution of phosphoric acid, always containing 1 to 3 % of aluminium, which is essential to the cement-forming reaction (Table 6.2). Zinc is often found in amounts that range from 0 to 10% to moderate the reaction. Whereas zinc is present as simple ions, aluminium forms a series of complexes with phosphoric acid (Section 6.1.1). This has important consequences, as we shall see, in the cement-forming reaction. 

Dental silicate cement liquids are concentrated aqueous solutions of orthophosphoric acid generally containing aluminium and zinc (Wilson, Kent Batchelor, 1968 Kent, Lewis Wilson, 1971a,b Wilson et al., 1972). The optimum orthophosphoric acid concentration is 48 to 55 % by mass (Wilson et al, 1970a), although higher concentrations are encountered. Aluminium is present as phosphate complexes and zinc as a simple ion (see Section 6.1.2). Examples are given in Table 6.6. 

Proteins that are polyampholytes, upon addition of electrolyte, first undergo some salting in up to a certain ionic strength, since electrostatic interactions between ions are shielded by the additional simple ions of both sign. Adding more salt will then cause salting out as the added ions compete for water that would otherwise solvate the protein. 

Solvent and Simple Ion-Stabilized Metal Nanoclusters Chemical Synthesis and Application... 

This chapter will mainly deal with the advantages of the alkaline EG synthesis method for the chemical preparation of noble metal nanoclusters stabilized by EG and simple ions, as well as the excellent performances of the functional materials assembled using these unprotected metal nanoclusters as building blocks. 

A strategy to solve this problem is to separate the core formation process from the reduction of metal ions in the cores as shown in Scheme 1, and use solvent (EG) and simple ions (OH , etc.) as the stabilizers [11]. In the first step of this process, metal salts hydrolyzed in the alkaline solution of EG to give rise to metal hydroxide or oxide colloids, which were then reduced by EG at elevated temperature to produce colloidal metal nanoclusters in the... 

Synthesis of Metal Nanoclusters Stabilized by Ethylene Glycol and Simple Ions... 

Figure 1. TEM images and size distributions of Pt, Rh and Ru nanoclusters stabilized by EG and simple ions [11] (a) Pt nanoclusters (0.37g/1) (b) Pt nanoclusters (3.7g/1) (c) Rh nanoclusters (0.31 g/1) (d) Ru nanoclusters (0.32g/1). (Reprinted from Ref [11], 2000, with permission from American Chemical Society.)...

Figure 3. TEM image and size distribution of Pt/Ru bimetallic nanoclusters (1.85g/l) stabilized by EG and simple ions [13].

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