E/2 mass spectrum: Difference between revisions

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Processes of the charge-stripping type  
Processes of the [[charge-stripping]] type  


::m<sup>+</sup> + N ?????????????????????????? m<sup>2+</sup> + N + e<sup>-</sup>  
::m<sup>+</sup> + N ?????????????????????????? m<sup>2+</sup> + N + e<sup>-</sup>  
that occur in a collision cell (containing a gas, N) located in a field-free region preceding a magnetic and electric sector combination placed in either order may be detected as follows: If the instrument slits are wide, and if the electric sector field E is set to half the value required to transmit the main ion-beam, the only ions to be transmitted will be those with a kinetic energy-to-charge ratio half that of the main ion-beam. The product ions of the charge-stripping process fulfil this condition. If the magnetic field B is scanned, a mass spectrum of such doubly charged product ions, and thus their singly charged precursors, is obtained. Such a spectrum is called an E/2 mass spectrum. Interference from product ions from processes of the type  
that occur in a collision cell (containing a gas, N) located in a [[field-free region]] preceding a magnetic and [[electric sector]] combination placed in either order may be detected as follows: If the instrument slits are wide, and if the [[electric sector]] field E is set to half the value required to transmit the main ion-beam, the only ions to be transmitted will be those with a kinetic energy-to-charge ratio half that of the main ion-beam. The [[product ion]]s of the [[charge-stripping]] process fulfil this condition. If the magnetic field B is scanned, a [[mass spectrum]] of such doubly charged [[product ion]]s, and thus their singly charged precursors, is obtained. Such a spectrum is called an E/2 mass spectrum. Interference from [[product ion]]s from processes of the type  


::m<sub>1</sub><sup>+</sup> + N ?????????????????????????? m<sub>2</sub><sup>+</sup> + N + (m<sub>1</sub>-m<sub>2</sub>)  
::m<sub>1</sub><sup>+</sup> + N ?????????????????????????? m<sub>2</sub><sup>+</sup> + N + (m<sub>1</sub>-m<sub>2</sub>)  
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== Related Terms ==
== Related Terms ==


[[2e Mass Spectrum]]
*[[2e Mass Spectrum]]


[[Category:Reactions]]
[[Category:Reactions]]


[[Category:Sequential m/z Separation]]
[[Category:Sequential m/z Separation]]

Revision as of 17:51, 1 December 2005

DRAFT DEFINITION
E/2 mass spectrum

Processes of the charge-stripping type

m+ + N ?????????????????????????? m2+ + N + e-

that occur in a collision cell (containing a gas, N) located in a field-free region preceding a magnetic and electric sector combination placed in either order may be detected as follows: If the instrument slits are wide, and if the electric sector field E is set to half the value required to transmit the main ion-beam, the only ions to be transmitted will be those with a kinetic energy-to-charge ratio half that of the main ion-beam. The product ions of the charge-stripping process fulfil this condition. If the magnetic field B is scanned, a mass spectrum of such doubly charged product ions, and thus their singly charged precursors, is obtained. Such a spectrum is called an E/2 mass spectrum. Interference from product ions from processes of the type

m1+ + N ?????????????????????????? m2+ + N + (m1-m2)

where m2 = 0.5 m1, can arise in E/2 mass spectra.


Considered between 2004 and 2006 but not included in the 2006 PAC submission
This is an unofficial draft definition presented for information and comment.

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Orange Book Entry

M2+ + X → M+ + X+

Processes of the charge-stripping type: M+ + X → M2+ + X + e occurring in collision cell (containing gas X) located in a field-free region preceding a magnetic and electric sector combination placed in either order, may be detected as follows;- if the instrument slits are wide and if the electric sector field is set to half the value required to transmit the main ion beam, the only ions transmitted will be those with kinetic energy/charge ratio half, or almost half, that of the main ion beam. The product ions of the above charge stripping process fulfil that condition. If the magnetic field, B, is scanned, a mass spectrum of such doubly-charged product ions and thus of their singly-charged precursors is obtained. Such a spectrum is termed a E/2 mass spectrum.

Related Terms