Mass Spectrometry
Base peak Thesignalwiththegreatest abundance in themass spectrum
Thesignalproduced
bythemolecular ion
Molecularion peak
Mtl peak A peak produced due tothemolecular ion containing a
C 13 isotope 1 ofnaturaloccurring c
Fragmentation ion A positivelychargedionproducedwhenthemolecularionbreaksapart
PE stream
ofcharged particles movingthrough field will bedeflected
a magnetic
according totheir mass charge m 2 ratio
Whatis it used
Stages
of Mass Spectrometry
ionisation
for
find relative isotopric abundances
acceleration Tofind RMM
deflection Determine structure
detection Identify impurities
ionisationeqn Mtcg e
eg Mcgs
RMM
flew Rmm
Graphs
µ
of
mass isotope relativeabundance
relativeabundances
RMM 24 79 2 10 26 11
10 11
24 25 26 2431
diatompin
tax sits element
may
isotope
give
0
go 160
, 57
Base Mass Spectra
IF a FEW
me
so
of
molecules
Petersen
to go cInserts
Molecular ion Ch ChCockyCnzt
Molecularion
peak 86 normallylastpeak moleculeswith It charge
Base Peak 57 tallestpeak
the
removingan electronfrom molecule can weakensome the
Fragmentation
remaining bonds causing themoleculetobreakapartor fragment
of
Fragment ion A positively charged ion produced whenthe molecular ion
breaks
apart
Note
1 Moleculesfragment as theyare ionised
2 Afewremain intacttogive themolecularionpeak
3 Thetendency ofthe molecule tofragmentincreases as their length increases
4 Thebase peak represents the most stablefragment
Base peak Thesignalwiththegreatest abundance in themass spectrum
Thesignalproduced
bythemolecular ion
Molecularion peak
Mtl peak A peak produced due tothemolecular ion containing a
C 13 isotope 1 ofnaturaloccurring c
Fragmentation ion A positivelychargedionproducedwhenthemolecularionbreaksapart
PE stream
ofcharged particles movingthrough field will bedeflected
a magnetic
according totheir mass charge m 2 ratio
Whatis it used
Stages
of Mass Spectrometry
ionisation
for
find relative isotopric abundances
acceleration Tofind RMM
deflection Determine structure
detection Identify impurities
ionisationeqn Mtcg e
eg Mcgs
RMM
flew Rmm
Graphs
µ
of
mass isotope relativeabundance
relativeabundances
RMM 24 79 2 10 26 11
10 11
24 25 26 2431
diatompin
tax sits element
may
isotope
give
0
go 160
, 57
Base Mass Spectra
IF a FEW
me
so
of
molecules
Petersen
to go cInserts
Molecular ion Ch ChCockyCnzt
Molecularion
peak 86 normallylastpeak moleculeswith It charge
Base Peak 57 tallestpeak
the
removingan electronfrom molecule can weakensome the
Fragmentation
remaining bonds causing themoleculetobreakapartor fragment
of
Fragment ion A positively charged ion produced whenthe molecular ion
breaks
apart
Note
1 Moleculesfragment as theyare ionised
2 Afewremain intacttogive themolecularionpeak
3 Thetendency ofthe molecule tofragmentincreases as their length increases
4 Thebase peak represents the most stablefragment
