Product ions singly-charged

Table 8.62 shows the main characteristics of ICP-MS, which is widely used in routine analytical applications. The ICP ion source has several unique advantages the samples are introduced at atmospheric pressure the degree of ionisation is relatively uniform for all elements and singly charged ions are the principal ion product. Theoretically, 54 elements can be ionised in an ICP with an efficiency of 90 % or more. Even some elements that do not show ionic emission lines should be ionised with reasonable efficiency (namely, As, 52 % and P, 33%) [381]. This is one of the advantages of ICP-MS over ICP-AES. Other features of ICP-MS that make it more attractive than ICP-AES are much lower detection limits ability to provide isotopic ratio information and to offer isotope dilution capabilities for quantitative analysis and clean and simple spectra. The... 

Figure 6.6. Chemical structures of selected product ions. Note they already carry a single charge.

Figure 6.16. Annotated product ion spectra from Fig. 6.14—singly-charged precursor.

Ion a charged species created when an atom or group of atoms gains or loses electrons Ion-Dipole Force intermolecular force between an ion and a dipole Ion Pair in a solution when a positive and negative ion exist as a single particle Ion Product Constant in an ionic reaction, the product of each ion s concentration in solution raised to a power equal to the coefficient in the net ionic equation, for water it equals [H+][OH ]... 

Besides space charge, image quality is limited by the combination of the number of pixels of the CCD camera and the size of a single ion event. The PSD usually employs two micro-channel plates (MCPs) mounted in a chevron configuration and backed by a phosphor screen. A product ion causes an electron cascade through the channel plates and onto the phosphor, which emits a pulse of diffuse light that must be focused properly onto the CCD array with a camera lens or fiber optic taper. In this process one product ion results in a signal on the CCD that is usually several pixels... 

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