Of single charged atomic ions

A SSIMS spectrum, like any other mass spectrum, consists of a series of peaks of dif ferent intensity (i. e. ion current) occurring at certain mass numbers. The masses can be allocated on the basis of atomic or molecular mass-to-charge ratio. Many of the more prominent secondary ions from metal and semiconductor surfaces are singly charged atomic ions, which makes allocation of mass numbers slightly easier. Masses can be identified as arising either from the substrate material itself from deliberately introduced molecular or other species on the surface, or from contaminations and impurities on the surface. Complications in allocation often arise from isotopic effects. Although some elements have only one principal isotope, for many others the natural isotopic abundance can make identification difficult. 

In the case of a singly charged atomic ion in aqueous solution we have estimated the mutual potential energy between the ion and an adjacent water molecule when they are of nearly the same size, and have found the value to be about four times as great as the mutual potential energy of two adjacent water molecules. We conclude then that in the vicinity of an atomic ion the water structure will have to build itself round the ion, insofar as this is possible. 

The first ionisation energy (IEO is the energy required to remove one mole of electrons from one mole of gaseous atoms of an element, to form one mole of singly charged positive ions ... 

Let us point out another aspect of the classification of compounds as ionic or covalent. Not all ions consist of single charged atoms. Many are small groups of atoms that are covalently bonded together, yet they still have excess positive or negative charge. Examples of such.polyatomic ions are ammonium ion, NH4+, sulfate ion, and nitrate ion,... 

Information on rate constants of charge-transfer reactions of singly charged atomic and molecular ions in the thermal and slightly hyperthermal range has... 

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