Mass Frontier allows you to calculate the possible elemental composition for any spectral peak displayed in Database Manager and Chromatogram Processor windows by simple peak picking. The advantage of this method compared to manual entering of the m/z value is that all the decimal places will be accurately transferred to Formula Generator and the m/z tolerance value will be automatically calculated from the source spectra if this option is enabled in the Acquired from Source check box.

To generate possible formulas for a peak, follow these steps:

1. Click on the Option button and review the predefined settings. Special attention should be given to the Charge setting (Limits tab) according to the polarity of your MS mode used for spectra acquisition. Be sure to also check the maximum number of elements used for calculation in the Elements in Use tab.
   
   
2. Click on the Pick a Peak button . The Formula Generator window will minimize to a bar
   
   
3. Click on a spectral peak in Database Manager or the Chromatogram Processor window
   
   
4. A list of possible formulas will be displayed