Vd. Kurochkin, CALCULATION OF INTENSITIES OF MOLECULAR INTERFERENCES IN GD-MS - APPLICATION TO ANALYSIS OF ALUMINUM-ALLOYS, Analytical communications, 33(10), 1996, pp. 381-384
A method for calculating the concentration of molecular ions in GD-MS
is reported. The method is based on measurements of effective stabilit
y factors (ESF) of molecular ions. ESPs have been measured for various
types of molecular ions: combination of Ar with gases and components
of the sample; components with each other and gases. An investigation
was carried out, by using a cryo-cooled pin-cell, on 5 aluminium stand
ard materials. It is shown that ESFs for different types of molecular
ions lie in the small range 1 x 10(-9)-10(-8) ppm(-1), except for ArH, hydrides, oxides and nitrides of metals. Comparison with reaction ra
te constants show that polarization grip of an atom by an ion is mainl
y responsible for more or less uniform values of ESFs. With use of thi
s method a program for mathematical simulation of mass-spectra was dev
eloped. The relative errors of calculated intensities of interferences
do not exceed the 15% level. The method provides a way for more accur
ate estimations of unresolved interferences and gives a comprehensive
idea of the spectrum in a given region.