Reactive, Air Sensitive Compounds

require

soft ionization and

strict exclusion of air or/and moisture

 

 

LIFDI complies with both requirements without experimental effort.

LIFDI spectra exhibit M^·+ions of very air sensitive compounds like

 
[{({iPr₂(C₆H₃)}₂nacnac)Cr}₂(μ-Ph)(μ-H)] ¹

        

The anaerobic LIFDI protocol (ca. 30 s) is very easy to apply:

 
1.  hold orifice of LIFDI capillary in inert headspace gas for some rinsing (ca. 5-10 s)

2.  dip LIFDI capillary into sample solution (ca. 1-2 s)

3.  keep orifice of LIFDI capillary in inert headspace and observe sample loading from capillary to emitter on CCTV screen (ca. 10-20 s incl. solvent evaporation)

Collect spectra as usual

Details of the LIFDI technique are described in the literature^2-4.

 

1)  Wesley H. Monillas, Glenn P. A. Yap, and Klaus H. Theopold, A Tale of Two Isomers: A Stable Phenyl Hydride and a High-Spin (S=3) Benzene Complex of Chromium
Angew. Chem. Int. Ed. 2007, 46, 6692-6694

 

2)  H. Bernhard Linden, Liquid injection field desorption ionization: a new tool for soft ionization of samples including air sensitive catalysts and non-polar hydrocarbons
Eur. J. Mass Spectrom. 2004, 10, 459-468

 

3)  H. Bernhard Linden, Liquid Injection Field Desorption Ionization (LIFDI), principles and applications
Encyclopedia of Mass Spectrometry, Elsevier Publishers, 2006, 8, 359-371

 

4)  J.H. Gross, N. Nieth, H.B. Linden, U. Blumbach, F.J. Richter, M. E. Tauchert, R.Tompers and P. Hofmann, Liquid injection field desorption/ionization of reactive transition metal complexes
Anal. Bioanal. Chem., 2006, 386, 52-58