Automated Identification of Ions Observed in Mass Spectra of Inorganic Compounds Using Isotopic Distribution Brute Force: Methodology and Performance Measurements

This Article describes the method of isotopic distribution brute force, which can be used to identify ions registered in mass spectra of inorganic compounds in an automated manner when a library search cannot be conducted. A detailed description of the isotopic distribution brute force methodology is presented, including a discussion of computation-related difficulties. The ability of the proposed algorithm to identify various inorganic ions is tested on a small set of real-life low-resolution mass spectra of lead halides and copper halides. An evaluation of the isotopic distribution brute force performance is conducted using the low-resolution experimental mass spectra of natural rhenium sulfide and lead(II) chloride. Based on identification results and obtained performance measurements, we formulate the empirical restrictions on the input data, ensuring that the application of isotopic distribution brute force is feasible from the standpoints of search space reduction and identification time.

Surface Imaging in Applied Research

Abstract

The possibilities of mass spectrometric visualization in new areas of research are considered. It is shown that surface mass spectrometry can be used to study structural materials and monitor surfaces for corrosion damage, process contamination, and damage. The possibility of studying non-metallic materials is shown for the first time. It is found that studying the low molecular weight part of polymer films helps to detect technological impurities and irreversible deformation of the film surface. It is established this can be used to authenticate handwritten documents, make corrections to them, and successfully compete with the classical means of such research.