Information at different resolving powers

Different resolving powers of the mass spectrometer allow various levels of information to be obtained. Remember that for all mass spectrometers the resolving power does not vary in the same way for different masses  

Increasing the resolving power for the detection of peaks from ubiquidn (C37sLL,3oN i05(111 sS). Redrawn from data in Marshall A.G., Hendrickson C.L. and Shi S.D.H., Anal. Chem., 74, 253A-259A, 2002. 

The difference in shift between the two formulae is 4.0134 - 4.0034 = 0.0100 u. Taking into account the charge state, the m/z difference to measure is 0.01/9 = 0.001 lu. The required resolving power is 952.6/0.0011 = 875 340. In 2006, only a high-field FTICR is capable of such a resolution. 

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