isopat (version 1.0)

isopat-package: Calculation of isotopic pattern of a chemical formula.

Description

The function calculates the isotopic pattern (fine structures) for a given chemical formula. It returns a list of accurate masses, abundances and isotopic compositions. The elements used and their isotopic characteristics can be defined by the user.

Details

ll{ Package: isopat Type: Package Version: 1.0 Date: 2011-04-05 License: GPL-2 LazyLoad: yes } Starting from a monoisotopic peak of a given molecule, the isotopic compositions and the concomitant abundances of isotopologues are changed iteratively towards less abundant isotopes over a number of generations 1,...,i,...,n. At each generation level i, a number i of isotopes contained in the monoisotopic peak have been exchanged for less abundant isotopes over all possible combinatorial changes of size i. Thus, generations of isotopic compositions are derived from an initial monoisotopic peak (i=0) while progressing to less abundant isotope compositions of a molecule.

See Also

isopattern iso_list

Examples

## calculate isotopic peaks for coffein-D9 #####################################
data(iso_list);
isopattern(iso_list,"C8H1N4O2D9",1e-10);