HP 5973 MSD Hardware Manual page 27

Reagent gas proton affinities
Species Proton affinity
kcal/mole
H 100
2
CH 127
4
C H 160
2 4
H O 165
2
H S 170
2
CH OH 182
3
i-C H 195
4 10
NH 207
3
Proton affinities of selected organic compounds for PCI
Molecule Proton affinity
(kcal/mole)
Acetaldehyde
Acetic acid
Acetone
Benzene
2-Butanol
Cyclopropane
Dimethyl ether
Ethane
Ethyl formate
Formic acid
Hydrobromic acid
Hydrochloric acid
Isopropyl alcohol
Methanol
Reactant ion formed
+
( m/z 3)
H
3
+
( m/z 17)
CH
5
+
( m/z 29)
C H
2 5
+
( m/z 19)
H O
3
+
( m/z 35)
H S
3
+
( m/z 33)
CH OH
3 2
+
t-C H ( m/z 57)
4 9
+
( m/z 18)
NH
4
Molecule
185 Methyl amine
188 Methyl chloride
202 Methyl cyanide
178 Methyl sulfide
197 Methyl cyclopropane
179 Nitroethane
190 Nitromethane
121 n-Propyl acetate
198 Propylene
175 Toluene
140 trans-2-Butene
141 Trifluoroacetic acid
190 Xylene
182
 Chemical Ionization Theory
3RVLWLYH &, WKHRU\
Proton affinity
(kcal/mole)
211
165
186
185
l80
185
180
207
179
187
180
167
187
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