The infrared spectra for the gaseous and liquid states, and the Raman spectra for the liquid state, including intensity and polarization data, are reported for ethyl cyanide (C2H5CN). A normal coordinate treatment has been made for four planar and five nonplanar skeletal vibrational modes. The observed spectra are in accord with a C8 model for this molecule. A complete assignment of frequencies to the fundamental modes of vibration is made for ethyl cyanide. From the spectroscopic data, the height of the barrier hindering internal rotation is estimated to be 5200 cal. The thermodynamic functions for ethyl cyanide have been calculated to 1000°K.

1.
G. Herzberg, Molecular Spectra and Molecular Structure, II (D. Van Nostrand Company, Inc., New York, 1945).
2.
F.
Halverson
and
R. J.
Francel
,
J. Chem. Phys.
17
,
694
(
1949
).
3.
R. M.
Badger
and
S. H.
Bauer
,
J. Am. Chem. Soc.
59
,
303
(
1937
).
4.
P.
Venkateswarlu
,
J. Chem. Phys.
20
,
923
(
1952
).
5.
H.
Gunthard
and
E.
Kovats
,
Helv. Chim. Acta
35
,
1190
(
1952
).
6.
Halverson
,
Stamm
, and
Whalen
,
J. Chem. Phys.
16
,
808
(
1948
).
7.
P.
Barchewitz
and
M.
Parodi
,
Compt. Rend.
209
,
30
(
1939
).
8.
R.
Kitson
and
N.
Griffith
,
Anal. Chem.
24
,
334
(
1952
).
9.
A.
Dadieu
and
K.
Kohlrausch
,
Monatsh.
56
,
461
(
1930
).
10.
A.
Reitz
and
R.
Skrabal
,
Monatsh.
70
,
398
(
1937
).
11.
L.
Howlett
,
Can. J. Research
4
,
80
(
1931
).
12.
B.
Bishui
,
Indian J. Phys.
22
,
167
(
1948
).
13.
R.
Dreisbach
and
R.
Martin
,
Ind. Eng. Chem.
41
,
2875
(
1949
).
14.
The Perkin‐Elmer Model 21 double‐beam infrared spectrometer was made available through the courtesy of Dr. Frederick C. Nachod of the Sterling‐Winthrop Research Institute, Rensselaer, New York.
15.
B.
Crawford
and
W.
Horowitz
,
J. Chem. Phys.
15
,
268
(
1947
).
16.
J. C.
Decius
,
J. Chem. Phys.
17
,
1315
(
1949
).
17.
R.
Rasmussen
,
J. Chem. Phys.
16
,
712
(
1948
).
18.
J. C.
Decius
,
J. Chem. Phys.
16
,
1025
(
1948
).
19.
B.
Crawford
,
J. Chem. Phys.
8
,
273
(
1940
).
20.
J.
Hirschfelder
,
J. Chem. Phys.
8
,
431
(
1940
).
21.
N.
Sheppard
and
D.
Simpson
,
Quart. Revs. (London)
7
,
22
(
1953
).
22.
J. R.
Nielsen
,
Phys. Rev.
40
,
445
(
1932
).
23.
K. S.
Pitzer
,
Discussions Faraday Soc.
10
,
66
(
1951
).
24.
J. G.
Aston
,
Discussions Faraday Soc.
10
,
73
(
1951
).
25.
Smith
,
Saunders
,
Nielsen
, and
Ferguson
,
J. Chem. Phys.
20
,
847
(
1952
).
26.
E.
Hurdis
and
C. P.
Smyth
,
J. Am. Chem. Soc.
65
,
89
(
1943
).
27.
F. D. Rossini, Chemical Thermodynamics (John Wiley and Sons, Inc., New York, 1950).
28.
K.
Pitzer
and
W.
Gwinn
,
J. Chem. Phys.
10
,
428
(
1942
).
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