Improving Match probability

This topic describes how to improve Match probability with library compounds.

Restrict m/z Range

Serves for narrowing the m/z range to be searched. In the case, you know approx. m/z you are interested in, you can omit the rest of the m/z and thus raise the Match probability. In case you enter wrong m/z range, a dialog will appear and will tell you what the m/z range of the current chromatogram is.

Use Selected m/z

Defines what m/z should or should not be searched.

• Search Only Selected will search only for the defined m/z. Suitable when you know typical m/z for the compounds you are interested in.
• Search All But Selected will omit selected m/z from search. Suitable e.g. when you don't want the used solvent to interfere with the search results.

Background subtraction

Defines exact points and/or intervals of retention time to be omitted from the search. Such values can be inserted manually or selected directly in the graph.

Preview Spectrum in Library

Shows the search results, based on the above-mentioned options, directly in the NIST library. You can check here, whether your setting were right, or even find out the typical m/z for selected compounds.