molecular ion


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molecular ion

An ion formed by removing (positive ion), or adding (negative ion), one or more electrons from a molecule M to form M• or M••.  The mass of the molecular ion corresponds to the molecule’s nominal or monoisotopic mass; the mass of the electron added or lost is usually inconsequential. The molecular ion mass is the sum of the relative masses of the most abundant naturally occurring isotopes of the various atoms comprising the molecule.
References in periodicals archive ?
Another important peak at m/z 190 was observed due to simultaneous loss of the side chain and two H-atoms (M - C5H11O + 2H) from the molecular ion which revealed the attachment of C5H11O unit to the indole nucleus (Fig.
html) a study published Wednesday in the journal Nature, a team of physicists from the National Institute of Standards and Technology (NIST) in Boulder, Colorado, describe a successful attempt at using previously known techniques to cool and control molecular ions.
The structure of the synthesized compound was characterized with GC-MS which gave the molecular ion peak at m/z=260, corresponding to molecular formula of the compound C14H16N2O3, as recorded in Table-3
The fragmentation of the main peaks include the fragmentations of cellulose xanthate and monomer (VP) and the base peak at m/e 112 where the molecular ion peak of monomer added hydrogen atom.
The tandem mass spectrometry (MS/MS) analysis was performed by using selected reaction monitoring (SRM) of the protonated molecular ions for the analytes, and scanning the targeted ions and fragment ions in a single segment.
As we promised not to give any quantitative estimation based on molecular ion mass peak intensity, we can only comment that these structures could be molecules that are preferably formed as (a) and (c), or are presumably stable diquinones like (b), which gave the third intensive mass peak (the structure marked as 2XZ trimeric qq) in the reaction mixture of 2,5-dimethylresorcinol together with resorcinol after the dimeric monoquinone marked as XZ dimeric rq and tetrameric monoquinone marked as 2X2Z tetrameric hq.
Observation of the infrared spectrum of helium-hydride molecular ion 4He[H.
Du, Interferences in photodetachment of a negative molecular ion,Commun.
The mass spectra showed the molecular ion peak at m/z [M.
started the molecular ion trend seven years ago, when he wondered how he could design an experiment from scratch to detect the electron electric dipole moment.

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