Elemental Composition Workshop

The Elemental Composition Workshop allows you to calculate the possible elemental compositions for any mass (integer or exact mass) or isotopic ratios.

• Calculate elemental compositions from measured isotope ratios. One fragment loss can be defined to deal with overlapping isotopic distributions such as M^+. and [M-H]⁺.

• Combine an exact mass measurement with measured isotope ratios to eliminate unreasonable compositions.
• Enter the elemental limits, constraints, and tolerances in a simple, easy-to-understand manner.
• Input mass spectra from text files for display and processing.
• Use thresholding and exclusion lists to omit noise or background and reference peaks from the calculation.
• Print reports, save results to text files, cut-and-paste for use in other applications.
• Choose between long (verbose) and short (concise) report formats.

Elemental Composition Calculation for hexatriacontane (C₃₆H_74.) mass spectrum imported from a text file. All peaks with a relative abundance greater then 5% are calculated with the exception of perfluorokerosene peaks and background peaks specified in the exclusion list.

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Elemental Composition Calculation for chlopyrifos (C₉H₁₁NO₃Cl₃PS) by combining an exact mass measurement with measured isotope ratios to limit the number of compositions.

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