==== AMDIS ====
<abbr title="Automated Mass spectral Deconvolution and Identification System">AMDIS</abbr> - <color red>**A**</color>utomated <color red>**M**</color>ass spectral <color red>**D**</color>econvolution and <color red>**I**</color>dentification <color red>**S**</color>ystem

{{:chemdata:amdis1.png?nolink}}

<abbr title="Automated Mass spectral Deconvolution and Identification System">AMDIS</abbr> was developed as a tool to specifically allow gas-chromatography with mass spectral analysis (GC/MS) to be performed during confidential inspections under the Chemical Weapons Convention.  It’s real value for most users in automating the complex process of extracting data from GC/MS data file.

=== How does this work ===

<abbr title="Automated Mass spectral Deconvolution and Identification System">AMDIS</abbr> works by finding all of the ions that rise and fall at the same time and associating them with a single component.  Once it has found this component it compares it to a library of spectra and retention indices that you have provided.{{:chemdata:amdisions.png}}


This is what a single component might look like when a larger component is eluting at the same time.  In this case the ion at m/z 83 does not have the same shape or time of maximization of the ions at m/z 111 and 158.  Thus the ions at 111 and 158 are considered part of the component and the ion at 83 is not. Notice that in this case the TIC (shown in white) doe not even indicate that there should be a component at ~9.36 minutes.


=== How can you get AMDIS ===


<abbr title="Automated Mass spectral Deconvolution and Identification System">AMDIS</abbr> is provided as a part of both the full NIST MS Database package as well as the demo NIST database. AMDIS can make use of the NIST database software if it is present, but it does not require the database software. In addition AMDIS can be downloaded  as a stand-alone program:

<WRAP center round download 80%>
  * [[https://chemdata.nist.gov/mass-spc/amdis/downloads/AMDIS_Installer-17.zip|Download AMDIS]]
  * Instructions for using AMDIS with NIST MS Search – <color red>11-25-2019</color>
    * {{chemdata:instructions_for_using_amdis_with_nistms.pdf|Acrobat PDF file}}
    * {{chemdata:instructions_for_using_amdis_with_nistms.pptx|PowerPoint Presentation}}
</WRAP>

Further discussions of AMDIS are available here:
  * [[chemdata:amdis_overview|An Overview of Automated GC/MS Identification]]
  * [[chemdata:amdisexplained|Automated Mass Spectral Deconvolution & Identification System]]