Plasma molecular species and matrix effects in the Hummer cavity microwave induced plasma optical emission spectrometry

The effect of matrix elements with ionization potentials from 5.72 to 10.48 eV (In, Ga, Cu, Pb, Cd, Bi, Zn, P) on atom and ion excitation temperatures, magnesium ratio, plasma molecular species and analytical signals more 30 trace elements in atmospheric pressure nitrogen microwave induced plasma (Agilent 4100 AES MP) have been studied. The concentration of matrix elements was varied in the range of 0–1% w·w⁻¹. It was shown that in the Hammer cavity, intensities of atomic and ionic lines with similar energies change in a similar way with increasing concentration of the matrix element. It was shown that, in general, the matrix effect doesn't correlate with the temperature. The Mg(II)/Mg(I) and both N₂⁺/OH and N₂⁺/N₂ correlates with the ionization potential of the matrix element and reflect the degree of its manifestation.