R: Stable isotopes

isotopes {enviPat} | R Documentation

## Stable isotopes

### Description

Dataframe with stable isotopes.

### Usage

    data(isotopes)

### Format

A data frame with 302 observations on the following 4 variables.

`element`

  Chemical element

`isotope`

  Stable isotopes of an element

`mass`

  Relative atomic mass

`abundance`

  Isotopic composition of an element

`ratioC`

  Maximum number of atoms of an element for one C-atom in a molecule, based on 99.99 % of case molecules.

### Details

The `ratioC`-value stems from a database survey conducted by Kind&Fiehn (2007); to disable, set value to 0. The list serves as input into several package nontarget-functions. The first column of the data frame also contains names of specific isotopes used for labeled compounds.

### Source

http://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl

### References

Kind, T. and Fiehn, O., 2007. Seven golden rules for heuristic filtering of molecular formulas obtained by accurate mass spectrometry. BMC Bioinformatics, 8:105.

### Examples

    data(isotopes)

[Package enviPat version 2.4 Index]