Charge inversion mass spectrum

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DRAFT DEFINITION
Charge inversion mass spectrum

Charge-inversion processes of the type

m+ + N ?????????????????????????? m- + N2+

or

m- + N ?????????????????????????? m+ + N + 2e-

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 connections to the two sectors, appropriate to transmission of either positive or negative main-beam ions, are simply reversed, the negative or positive product ions of the two processes, respectively, will be transmitted. If the magnetic field is scanned, a spectrum of such product ions will be obtained, and this spectrum is called a charge-inversion mass spectrum. These spectra are sometimes referred to as charge reversal, or as ??????????????????????????E and +E spectra, respectively.

The terms "2E, E/2, -E, or +E mass spectrum" should not be used without prior explanation of the meaning of 2E, E, +E and ??????????????????????????E.


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

Charge inversion processes of the types: M+ + X?????????????????????-, M - + X2+ or M - + X ?????????????????????- M+ + X + 2e respectively, occurring in a collision cell (containing a gas X) located in a field-free zone 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 connections to the two sectors, appropriate to transmission of either positive or negative main-beam ions, are simply reversed, the negative or positive product ions respectively will be transmitted. If the magnetic field is scanned a spectrum of such ions will be obtained and this is termed a charge-inversion spectrum. These are sometimes referred to as -E and +E spectra. Note: The terms ??????????????????????2E, E /2,-E or +E mass spectrum????????????????????????? should not be used without prior explanation of their meaning.


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