Experimental and Theoretical Study of the Manifestation of the Major Background Singly Charged ArM+ Argide Ions in Inductively Coupled Plasma Mass Spectrometry

Singly charged background argide ions ArH+, ArN+, ArO+, and Ar2+ create strong spectral interferences in elemental and isotopic analysis by inductively coupled plasma mass spectrometry (ICP MS). In this study, we experimentally investigated the behavior of these ions depending on variations in high-frequency plasma power and argon carrier gas flow rate. Theoretical analysis was performed using thermodynamic modeling to predict the behavior of these argide ions on changes in plasma temperature and argon flow rate. Common patterns in the intensity of these major background ions and changes in their formation efficiency at different working parameters of the ICP are noted. A good agreement between the observed experimental dependences and those derived from thermodynamic models is noted.