1. MASS SPECTROMETRY
(MS)
MS - routinely used in analysis of
composition of compounds. MS allows
the determination of mass of
individual ions....
Most common method for generation
of ions is electron impact – the
molecule is bombarded with a high
energy electron beam.
The ionised molecule (molecular ion)
results from the expulsion of (usually)
one electron and is therefore a radical
cation.
+• −
M→ M +e
fragmentation
, other positive ions + neutral
fragments
A plot of relative ion abundance vs
m/z
(m = mass of ion; z = charge of ion) is
the mass spectrum.
m/z →
The molecular ion (parent ion, M+•)
must be the ion of
highest m/z (z = 1).
(MS)
MS - routinely used in analysis of
composition of compounds. MS allows
the determination of mass of
individual ions....
Most common method for generation
of ions is electron impact – the
molecule is bombarded with a high
energy electron beam.
The ionised molecule (molecular ion)
results from the expulsion of (usually)
one electron and is therefore a radical
cation.
+• −
M→ M +e
fragmentation
, other positive ions + neutral
fragments
A plot of relative ion abundance vs
m/z
(m = mass of ion; z = charge of ion) is
the mass spectrum.
m/z →
The molecular ion (parent ion, M+•)
must be the ion of
highest m/z (z = 1).
