Difference between revisions of "Resolution (mass spectrometry)"

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From [[Standard Definitions of Terms Relating to Mass Spectrometry : A report from the Committee on Measurements and Standards of the American Society for Mass Spectrometry]]:
 
From [[Standard Definitions of Terms Relating to Mass Spectrometry : A report from the Committee on Measurements and Standards of the American Society for Mass Spectrometry]]:
  
'''Resolution: 10% valley definition''', m/?m. Let two peaks of equal height in a mass spectrum at masses m and m-?m ?m. It is usually a func- tion of m, therefore m/?m should be given for a number of values of m.  
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'''Resolution: 10% valley definition''', m/Δm. Let two peaks of equal height in a mass spectrum at masses m and m-Δmm Δm. It is usually a func- tion of m, therefore m/Δm should be given for a number of values of m.  
  
'''Resolution: peak width definition''', m/?m. For a single peak made up of singly charged ions at mass m in a mass spectrum, the resolution may be expressed as m/?m, where Am is the width of the peak at a height that is a specified fraction of the maximum peak height. It is recommended that one of three values 50%, 5%, or 0.5% be used. For an isolated symmetrical peak, recorded with a system that is linear in the range between 5% and 10% levels of the peak, the 5% width defmition is technically equivalent to the Photo-ionization. 10% valley defmition
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'''Resolution: peak width definition''', m/Δm. For a single peak made up of singly charged ions at mass m in a mass spectrum, the resolution may be expressed as m/Δm, where Am is the width of the peak at a height that is a specified fraction of the maximum peak height. It is recommended that one of three values 50%, 5%, or 0.5% be used. For an isolated symmetrical peak, recorded with a system that is linear in the range between 5% and 10% levels of the peak, the 5% width defmition is technically equivalent to the Photo-ionization. 10% valley definition
  
 
'''Resolving power (mass)'''. The ability to distinguish between ions differing slightly in mass-to-charge ratio. It may be characterized by giving the peak width, measured in mass units, expressed as a function of mass, for at least two points on the peak, specihcally for 50% and for 5% of the maximum peak height.
 
'''Resolving power (mass)'''. The ability to distinguish between ions differing slightly in mass-to-charge ratio. It may be characterized by giving the peak width, measured in mass units, expressed as a function of mass, for at least two points on the peak, specihcally for 50% and for 5% of the maximum peak height.

Revision as of 14:55, 11 May 2010