Oxides, Hydroxides, Hydrides, and Doubly Charged Species

Oxides, Hydroxides, Hydrides, and Doubly Charged Species 

Another type of spectral interference is produced by elements in the sample combining with H+, 0+, or OH+ (either from water or air) to form molecular hydrides (+ H+), oxides (+ 0+), and hydroxides (+ OH+), which occur at 1, 16, and 17 mass units, respectively, higher than the element s mass. These interferences are typically produced in the cooler zones of the plasma, immediately before the interface region. They are usually more serious when rare earth or refractory-type elements are present in the sample, because many of them readily form molecular species (particularly oxides), which create spectral overlap problems on other elements in the same group. If the oxide species is mainly derived from entrained air around the plasma, it can be reduced by either using an elongated outer tube to the torch or a metal shield between the plasma and the RF coil. 

Some Elements That Readily Form Oxides, Hydroxides, Hydrides, and Doubly Charged Species in the Plasma, Together with the Analytes Affected by the Interference 

Hydroxide, Hydride, Doubly Charged Species 

Practical Guide to ICP-MS A Tutorial for Beginners, Second Edition 

Another type of spectral interference is produced by elanents in the sample combining with H+ or OH+ (either from water or air) to form molecular hydrides (+ H+), oxides (+ 0), and hydroxides (+ which occur at 1,16, and 17 mass 

The final classification of spectral interferences is called isobaric overlaps, produced mainly by dififerent isotopes of other elements in the sample creating spectral interferences at the same mass as the analyte. For example, vanadium has two isotopes at 50 and 51 amu, respectively. However, mass 50 is the only practical isotope to use in the presence of a chloride matrix because of the large contribution from the inter- 

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