Formula prediction

Description

This module attempts to calculate all possible molecular formulas for a data point, using given elemental and heuristic constraints. For a detailed description of the functionality and the embedded algorithms, please see the following publication:
Pluskal T. et al, Highly Accurate Chemical Formula Prediction Tool Utilizing High-Resolution Mass Spectra, MS/MS Fragmentation, Heuristic Rules, and Isotope Pattern Matching. Anal Chem (2012), 84(10):4396-403.

Method parameters

Charge
The predicted charge of peaks to calculate the neutral mass.
Noise level
The minimum intensity of peaks to calculate a sum formula of.
Ionisation
The predicted ionisation of peaks. E.g. [M+] or [M+NH4]+
Neutral mass
The neutral mass is calculated from the peak m/z value, its charge and type of ionization adduct.
m/z tolerance
Tolerance of the neutral mass for searching the formula.
Elements
Elements allowed in the formula and their minimum and maximum counts.
Element count heuristics
Selection of heuristic restrictions on element counts.
RDBE restrictions
Selection of restrictions on RDBE (rings double bonds) values. .
Isotope pattern filter
If selected, only results which fit the required isotope pattern similarity score will be returned. Furthermore, the results will be ranked by descending isotope pattern score.
Display results
If enabled, the result will be displayed in the spectrum plot. If this is the last module in the processing list, the results will be displayed in any way.
Dataset color
Select the color, the results of this module shall be displayed in.