The ethyl radical has been isolated and spectroscopically characterized in 4He nanodroplets. The band origins of the five CH stretch fundamentals are shifted by < 2 cm−1 from those reported for the gas phase species [S. Davis, D. Uy, and D. J. Nesbitt, J. Chem. Phys.112, 1823 (2000) https://doi.org/10.1063/1.480746; T. Häber, A. C. Blair, D. J. Nesbitt, and M. D. Schuder, J. Chem. Phys.124, 054316 (2006) https://doi.org/10.1063/1.2140740]. The symmetric CH2 stretching band (v1) is rotationally resolved, revealing nuclear spin statistical weights predicted by G12 permutation-inversion group theory. A permanent electric dipole moment of 0.28 (2) D is obtained via the Stark spectrum of the v1 band. The four other CH stretch fundamental bands are significantly broadened in He droplets and lack rotational fine structure. This broadening is attributed to symmetry dependent vibration-to-vibration relaxation facilitated by the He droplet environment. In addition to the five fundamentals, three a1′ overtone/combination bands are observed, and each of these have resolved rotational substructure. These are assigned to the 2v12, v4 + v6, and 2v6 bands through comparisons to anharmonic frequency computations at the CCSD(T)/cc-pVTZ level of theory.

1.
J.
Warnatz
,
Combustion Chemistry
(
Springer
,
New York
,
1984
).
2.
J.
Villà
,
J. C.
Corchado
,
A.
González-Lafont
,
J. M.
Lluch
, and
D. G.
Truhlar
,
J. Phys. Chem. A
103
,
5061
(
1999
).
3.
J. A.
Miller
and
S. J.
Klippenstein
,
Phys. Chem. Chem. Phys.
6
,
1192
(
2004
).
4.
J. C.
Rienstra-Kiracofe
,
W. D.
Allen
, and
H. F.
Schaefer
 III
,
J. Phys. Chem. A
104
,
9823
(
2000
).
5.
J.
Agarwal
,
J. M.
Turney
, and
H. F.
Schaefer
 III
,
J. Phys. Chem. Lett.
2
,
2587
(
2011
).
6.
J.
Pacansky
and
M.
Dupuis
,
J. Chem. Phys.
68
,
4276
(
1978
).
7.
J.
Pacansky
,
W.
Koch
, and
M. D.
Miller
,
J. Am. Chem. Soc.
113
,
317
(
1991
).
8.
S.
Davis
,
D.
Uy
, and
D. J.
Nesbitt
,
J. Chem. Phys.
112
,
1823
(
2000
).
9.
T. J.
Sears
,
P. M.
Johnson
,
P.
Jin
, and
S.
Oatis
,
J. Chem. Phys.
104
,
781
(
1996
).
10.
T. J.
Sears
,
P. M.
Johnson
, and
J.
BeeBe-Wang
,
J. Chem. Phys.
111
,
9213
(
1999
).
11.
M.
Hartmann
,
R. E.
Miller
,
J. P.
Toennies
, and
A.
Vilesov
,
Phys. Rev. Lett.
75
,
1566
(
1995
).
12.
R. W.
Fessenden
and
R. H.
Schuler
,
J. Chem. Phys.
39
,
2147
(
1963
).
13.
J.
Pacansky
,
G. P.
Gardini
, and
J.
Bargon
,
J. Am. Chem. Soc.
98
,
2665
(
1976
).
14.
J.
Pacansky
,
D. E.
Horne
,
G. P.
Gardini
, and
J.
Bargon
,
J. Phys. Chem.
81
,
2149
(
1977
).
15.
J.
Pacansky
and
H.
Coufal
,
J. Chem. Phys.
71
,
2811
(
1979
).
16.
J.
Pacansky
and
M.
Dupuis
,
J. Am. Chem. Soc.
104
,
415
(
1982
).
17.
J.
Pacansky
and
B.
Schrader
,
J. Chem. Phys.
78
,
1033
(
1983
).
18.
G.
Chettur
and
A.
Snelson
,
J. Phys. Chem.
91
,
3483
(
1987
).
19.
T.
López-Ciudad
,
R.
Ramirez
,
J.
Schulte
, and
M. C.
Bohm
,
J. Chem. Phys.
119
,
4328
(
2003
).
20.
T.
Häber
,
A. C.
Blair
,
D. J.
Nesbitt
, and
M. D.
Schuder
,
J. Chem. Phys.
124
,
054316
(
2006
).
21.
P. M.
Johnson
and
T. J.
Sears
,
J. Chem. Phys.
111
,
9222
(
1999
).
22.
T. A.
Claxton
and
A. M.
Graham
,
J. Chem. Soc., Chem. Commun.
15
,
1167
(
1987
).
23.
T. A.
Claxton
and
A. M.
Graham
,
J. Chem. Soc., Faraday Trans. 2
83
,
2307
(
1987
).
24.
H. U.
Suter
and
T.-K.
Ha
,
Chem. Phys.
154
,
227
(
1991
).
25.
P. R.
Bunker
and
P.
Jensen
,
Molecular Symmetry and Spectroscopy
(
NRC Research
,
Ottawa
,
1998
).
26.
M.
Hartmann
,
F.
Mielke
,
J. P.
Toennies
,
A. F.
Vilesov
, and
G.
Benedek
,
Phys. Rev. Lett.
76
,
4560
(
1996
).
27.
P. L.
Raston
,
C. J.
Knapp
, and
W.
Jäger
,
Phys. Chem. Chem. Phys.
13
,
18789
(
2011
).
28.
P. L.
Raston
,
T.
Liang
, and
G. E.
Douberly
,
J. Chem. Phys.
137
,
184302
(
2012
).
29.
J.
Küpper
,
J. M.
Merritt
, and
R. E.
Miller
,
J. Chem. Phys.
117
,
647
(
2002
).
30.
K.
von Haeften
,
A.
Metzelthin
,
S.
Rudolph
,
V.
Staemmler
, and
M.
Havenith
,
Phys. Rev. Lett.
95
,
215301
(
2005
).
31.
A. M.
Morrison
,
P. L.
Raston
, and
G. E.
Douberly
, “
Rotational dynamics of the methyl radical in superfluid 4He nanodroplets
,”
J. Phys. Chem. A
(Published online: December 7,
2012
).
32.
P. L.
Raston
,
T.
Liang
, and
G. E.
Douberly
,
J. Chem. Phys.
138
,
174302
(
2013
).
33.
A. M.
Morrison
,
J.
Agarwal
,
H. F.
Schaefer
 III
, and
G. E.
Douberly
,
J. Phys. Chem. A
116
,
5299
(
2012
).
35.
J. P.
Toennies
and
A. F.
Vilesov
,
Angew. Chem., Int. Ed.
43
,
2622
(
2004
).
36.
A. M.
Morrison
,
T.
Liang
, and
G. E.
Douberly
,
Rev. Sci. Instrum.
84
,
013102
(
2013
).
37.
M. Y.
Choi
,
G. E.
Douberly
,
T. M.
Falconer
,
W. K.
Lewis
,
C. M.
Lindsay
,
J. M.
Merritt
,
P. L.
Stiles
, and
R. E.
Miller
,
Int. Rev. Phys. Chem.
25
,
15
(
2006
).
38.
A. M.
Morrison
,
S. D.
Flynn
,
T.
Liang
, and
G. E.
Douberly
,
J. Phys. Chem. A
114
,
8090
(
2010
).
39.
K.
Raghavachari
,
G. W.
Trucks
,
J. A.
Pople
, and
M. P.
Head-Gordon
,
Chem. Phys. Lett.
157
,
479
(
1989
).
40.
M. J. O.
Deegan
and
P. J.
Knowles
,
Chem. Phys. Lett.
227
,
321
(
1994
).
41.
C.
Hampel
,
K. A.
Peterson
, and
H.-J.
Werner
,
Chem. Phys. Lett.
190
,
1
(
1992
).
42.
J. D.
Watts
,
J.
Gauss
, and
R. J.
Bartlett
,
Chem. Phys. Lett.
200
,
1
(
1992
).
43.
J. D.
Watts
,
J.
Gauss
, and
R. J.
Bartlett
,
J. Chem. Phys.
98
,
8718
(
1993
).
44.
J. F.
Stanton
,
Chem. Phys. Lett.
281
,
130
(
1997
).
45.
T. H.
Dunning
,
J. Chem. Phys.
90
,
1007
(
1989
).
46.
H. H.
Nielsen
,
Rev. Mod. Phys.
23
,
90
(
1951
).
47.
D. A.
Clabo
 Jr.
,
W. D.
Allen
,
R. B.
Remington
,
Y.
Yamaguchi
, and
H. F.
Schaefer
 III
,
Chem. Phys.
123
,
187
(
1988
).
48.
J. F.
Stanton
,
C. L.
Lopreore
, and
J.
Gauss
,
J. Chem. Phys.
108
,
7190
(
1998
).
49.
J.
Agarwal
,
A. C.
Simmonett
, and
H. F.
Schaefer
 III
,
Mol. Phys.
110
,
2419
(
2012
).
50.
CFOUR, Coupled-Cluster Techniques for Computational Chemistry, a quantum-chemical program package by
J. F.
Stanton
,
J.
Gauss
,
M. E.
Harding
,
P. G.
Szalay
with Contributions from
A. A.
Auer
,
R. J.
Bartlett
,
U.
Benedikt
,
C.
Berger
,
D. E.
Bernholdt
,
Y. J.
Bomble
,
L.
Cheng
,
O.
Christiansen
,
M.
Heckert
,
O.
Heun
,
C.
Huber
,
T.-C.
Jagau
,
D.
Jonsson
,
J.
Jusélius
,
K.
Klein
,
W. J.
Lauderdale
,
D. A.
Matthews
,
T.
Metzroth
,
D. P.
O’neill
,
D. R.
Price
,
E.
Prochnow
,
K.
Ruud
,
F.
Schiffmann
,
W.
Schwalbach
,
S.
Stopkowicz
,
A.
Tajti
,
J.
Vázquez
,
F.
Wang
,
J. D.
Watts
and the Integral Packages Molecule,
J.
Almlöf
and
P. R.
Taylor
, PROPS,
P. R.
Taylor
, ABACUS
T.
Helgaker
,
H. J. Aa.
Jensen
,
P.
Jørgensen
, and
J.
Olsen
, and ECP Routines by
A. V.
Mitin
and
C.
Van Wüllen
, see http://www.cfour.de for the current version.
51.
H. C.
Longuet-Higgins
,
Mol. Phys.
6
,
445
(
1963
).
52.
See supplementary material at http://dx.doi.org/10.1063/1.4804435 for the table of anharmonic frequencies, the difference mass spectra, the ν1 band measured with different precursors and the simulation of the perpendicular bands, Table S1 and Figures S1, S2, and S3, respectively; a comprehensive account of the G12 permutation-inversion group treatment for ethyl radical is also provided.
53.
C. M.
Lindsay
and
R. E.
Miller
,
J. Chem. Phys.
122
,
104306
(
2005
).
54.
B.
Ruscic
,
J.
Berkowitz
,
L. A.
Curtiss
, and
J. A.
Pople
,
J. Chem. Phys.
91
,
114
(
1989
).
55.
J.
Pacansky
and
H.
Coufal
,
J. Chem. Phys.
72
,
5285
(
1980
).
56.
W. L.
Hase
,
H. B.
Schlegel
,
V.
Balbyshev
, and
M.
Page
,
J. Phys. Chem.
100
,
5354
(
1996
).
57.
Y.
Chen
,
A.
Rauk
, and
E.
Tschuikow-Roux
,
J. Chem. Phys.
93
,
6620
(
1990
).
58.
M. S.
Stark
,
J. Am. Chem. Soc.
122
,
4162
(
2000
).
59.
G. E.
Quelch
,
M. M.
Gallo
, and
H. F.
Schaefer
 III
,
J. Am. Chem. Soc.
114
,
8239
(
1992
).
60.
G. E.
Quelch
,
M. M.
Gallo
,
M.
Shen
,
Y.
Xie
,
H. F.
Schaefer
 III
, and
D.
Moncrieff
,
J. Am. Chem. Soc.
116
,
4953
(
1994
).
61.
I. S.
Ignatyev
,
Y.
Xie
,
W. D.
Allen
, and
H. F.
Schaefer
 III
,
J. Chem. Phys.
107
,
141
(
1997
).
62.
J. J.
Wilke
,
W. D.
Allen
, and
H. F.
Schaefer
 III
,
J. Chem. Phys.
128
,
074308
(
2008
).
63.
A. L. L.
East
and
P. R.
Bunker
,
Chem. Phys. Lett.
282
,
49
(
1998
).
64.
R. S.
Bhatta
,
A.
Gao
, and
D. S.
Perry
,
J. Mol. Struct.: THEOCHEM
941
,
22
(
2010
).
65.
J. F.
Stanton
, personal communication (
2013
).
66.
J.
Vazquez
and
J. F.
Stanton
,
Mol. Phys.
104
,
377
(
2006
).
67.
E. B.
Wilson
,
C. C.
Lin
, and
D. R.
Lide
,
J. Chem. Phys.
23
,
136
(
1955
).
68.
E.
Kim
and
S.
Yamamoto
,
J. Chem. Phys.
120
,
3265
(
2004
).
69.
G. O.
Sørensen
and
T.
Pedersen
,
Studies in Physical and Theoretical Chemistry, Vol. 23. Symmetries and Properties of Non-Rigid Molecules: A Comprehensive Survey
(
Elsevier
,
Amsterdam
,
1982
).
70.
C.
Callegari
,
K. K.
Lehmann
,
R.
Schmied
, and
G.
Scoles
,
J. Chem. Phys.
115
,
10090
(
2001
).
71.
K. K.
Lehmann
,
J. Chem. Phys.
114
,
4643
(
2001
).
72.
R. A.
Cowley
and
A. D. B.
Woods
,
Can. J. Phys.
49
,
177
(
1971
).
73.
K.
Nauta
and
R. E.
Miller
,
J. Chem. Phys.
115
,
8384
(
2001
).
74.
D. J.
Nesbitt
and
R. W.
Field
,
J. Phys. Chem.
100
,
12735
(
1996
).
75.
K.
Nauta
and
R. E.
Miller
,
J. Chem. Phys.
115
,
10254
(
2001
).
76.
A. G.
Csaszar
,
WIREs Comput. Mol. Sci.
2
,
273
(
2012
).
77.
I. M.
Mills
,
Molecular Spectroscopy: Modern Research
(
Academic Press
,
New York
,
1972
).
78.
C. M.
Western
, PGOPHER, a program for simulating rotational structure, University of Bristol, version: 7.1.108 (
2010
), see http://pgopher.chm.bris.ac.uk.

Supplementary Material

You do not currently have access to this content.