Relative Franck–Condon factors, determined from threshold electron photoionization experiments, are presented for methane, ethane, and propane. The data are compared with those obtained by photoelectron spectroscopy and photoionization mass spectrometry. Differences are attributed to autoionization, cross section variations with energy above threshold, and, in photoelectron spectroscopy experiments, variations in transmission of the energy analyzer.

1.
D.
Villarejo
,
J. Chem. Phys.
48
,
4014
(
1968
).
2.
J. A. R. Samson, Techniques of Vacuum Ultraviolet Spectroscopy (Wiley, New York, 1967), p. 214.
3.
D.
Villarejo
,
R.
Stockbauer
, and
M. G.
Inghram
,
J. Chem. Phys.
50
,
4599
(
1969
).
4.
A. D.
Baker
,
C.
Baker
,
C. R.
Brundle
, and
D. W.
Turner
,
J. Mass Spectry. Ion Phys.
1
,
285
(
1968
).
5.
H.
Sjögren
,
Phys. Letters
19
,
210
(
1965
).
6.
D.
Villarejo
,
R. R.
Herm
, and
M. G.
Inghram
,
J. Chem. Phys.
46
,
4995
(
1967
).
7.
J.
Berkowitz
and
W. A.
Chupka
,
J. Chem. Phys.
51
,
2341
(
1969
).
8.
W. A.
Chupka
,
J. Chem. Phys.
30
,
191
(
1959
).
9.
D. W.
Turner
and
D. P.
May
,
J. Chem. Phys.
45
,
471
(
1966
).
10.
J. Berkowitz and P. M. Guyon, J. Chem. Phys. (to be published).
11.
J. E.
Collin
and
P.
Natalis
,
J. Mass Spectry. Ion Phys.
1
,
121
(
1968
).
12.
W. A.
Chupka
and
J.
Berkowitz
,
J. Chem. Phys.
47
,
2921
(
1967
).
13.
D. W.
Turner
,
Proc. Roy. Soc. (London)
A307
,
15
(
1968
).
14.
C. R. Brundle (private communication).
This content is only available via PDF.
You do not currently have access to this content.