Cyanomethyl radical

Formula: C₂H₂N
Molecular weight: 40.0440
IUPAC Standard InChI: InChI=1S/C2H2N/c1-2-3/h1H2
IUPAC Standard InChIKey: XSTKDMFTWATIQP-UHFFFAOYSA-N
CAS Registry Number: 2932-82-3
Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
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Gas phase ion energetics data

Go To: Top, Vibrational and/or electronic energy levels, References, Notes

Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess

View reactions leading to C₂H₂N⁺ (ion structure unspecified)

Electron affinity determinations

EA (eV)	Method	Reference	Comment
1.530 ± 0.010	LPES	Goebbert, Velarde, et al., 2010	B
1.543 ± 0.014	LPES	Moran, Ellis, et al., 1987	B
1.59 ± 0.13	D-EA	Bartmess, Scott, et al., 1979	value altered from reference due to change in acidity scale; B
1.5600 ± 0.0060	LPD	Marks, Wetzel, et al., 1986	B
1.507 ± 0.018	LPD	Zimmerman and Brauman, 1977	B
>1.60 ± 0.20	EIAE	Tsuda, Yokohata, et al., 1971	From MeCN. G3MP2B3 calculations indicate an EA of ca. 1.5 eV; B

Ionization energy determinations

IE (eV)	Method	Reference	Comment
9.9 ± 0.1	DER	Holmes, Lossing, et al., 1993	LL
10.0	DER	Lias, Bartmess, et al., 1988	LL
10.9 ± 0.1	EI	Pottie and Lossing, 1961	RDSH
10.3 ± 0.02	EI	Holmes, Lossing, et al., 1993	Vertical value; LL

Vibrational and/or electronic energy levels

Go To: Top, Gas phase ion energetics data, References, Notes

Data compiled by: Marilyn E. Jacox

State: X

Vib. sym.	No.	Approximate type of mode	cm^-1	Med.	Method	References


a₁	3	CH₂ scissor	1432.3	Ar	IR	Cho and Andrews, 2011
	4	C-C stretch	1026.0	Ar	IR	Cho and Andrews, 2011
b₁	5	H₂CC OPLA	663.79	gas	PE DL	Moran, Ellis, et al., 1987 Sumiyoshi, Tanaka, et al., 1996
	5	H₂CC OPLA	664.6	Ar	IR	Cho and Andrews, 2011

Additional references: Jacox, 1994, page 250; Jacox, 1998, page 280; Jacox, 2003, page 264; Saito, Yamamoto, et al., 1988; Saito and Yamamoto, 1997; Ozeki, Hirao, et al., 2004

References

Go To: Top, Gas phase ion energetics data, Vibrational and/or electronic energy levels, Notes

Goebbert, Velarde, et al., 2010
Goebbert, D.J.; Velarde, L.; Khuseynov, D.; Sanov, A., C-H Bond Dissociation Energy of Malononitrile, J. Phys. Chem. Lett., 2010, 1, 4, 792-795, https://doi.org/10.1021/jz900379t . [all data]

Moran, Ellis, et al., 1987
Moran, S.; Ellis, H.B., Jr.; DeFrees, D.J.; McLean, A.D.; Ellison, G.B., Carbanion spectroscopy: CH₂CN^-, J. Am. Chem. Soc., 1987, 109, 5996. [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

Marks, Wetzel, et al., 1986
Marks, J.; Wetzel, D.M.; Comita, P.B.; Brauman, J.I., A dipole supported state in cyanomethyl anion, the conjugate base of acetonitrile. Rotational band assignments in the electron photodetachment spectrum of -CH₂CN, J. Chem. Phys., 1986, 84, 5284. [all data]

Zimmerman and Brauman, 1977
Zimmerman, A.H.; Brauman, J.I., Electron photodetachment from negative ions of C_2v symmetry. Electron affinities of allyl and cyanomethyl radicals, J. Am. Chem. Soc., 1977, 99, 3565. [all data]

Tsuda, Yokohata, et al., 1971
Tsuda, S.; Yokohata, A.; Umaba, T., Measurement of negative ions formed by electron impact. VIII. Ionization efficiency curves of negative ions from methyl and ethyl cyanides, Bull. Chem. Soc. Jpn., 1971, 44, 1486. [all data]

Holmes, Lossing, et al., 1993
Holmes, J.L.; Lossing, F.P.; Mayer, P.M., The effects of methyl substitution on the structure and thermochemistry of the cyanomethyl radical and cation, Chem. Phys. Lett., 1993, 212, 134. [all data]

Lias, Bartmess, et al., 1988
Lias, S.G.; Bartmess, J.E.; Liebman, J.F.; Holmes, J.L.; Levin, R.D.; Mallard, W.G., Gas-phase ion and neutral thermochemistry, J. Phys. Chem. Ref. Data, Suppl. 1, 1988, 17, 1-861. [all data]

Pottie and Lossing, 1961
Pottie, R.F.; Lossing, F.P., Free radicals by mass spectrometry. XXV. Ionization potentials of cyanoalkyl radicals, J. Am. Chem. Soc., 1961, 83, 4737. [all data]

Cho and Andrews, 2011
Cho, H.-G.; Andrews, L., Matrix Infrared Spectra and Density Functional Calculations of the H, J. Phys. Chem. A, 2011, 115, 31, 8638, https://doi.org/10.1021/jp204887y . [all data]

Sumiyoshi, Tanaka, et al., 1996
Sumiyoshi, Y.; Tanaka, K.; Tanaka, T., Time-resolved infrared diode laser spectroscopy of the ν5 band of the cyanomethyl radical (H2CCN), J. Chem. Phys., 1996, 104, 5, 1839, https://doi.org/10.1063/1.471709 . [all data]

Jacox, 1994
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules, American Chemical Society, Washington, DC, 1994, 464. [all data]

Jacox, 1998
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement A, J. Phys. Chem. Ref. Data, 1998, 27, 2, 115-393, https://doi.org/10.1063/1.556017 . [all data]

Jacox, 2003
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement B, J. Phys. Chem. Ref. Data, 2003, 32, 1, 1-441, https://doi.org/10.1063/1.1497629 . [all data]

Saito, Yamamoto, et al., 1988
Saito, S.; Yamamoto, S.; Irvine, W.M.; Ziurys, L.M.; Suzuki, H.; Ohishi, M.; Kaifu, N., Laboratory detection of a new interstellar free radical CH2CN(2B1), Astrophys. J., 1988, 334, L113, https://doi.org/10.1086/185324 . [all data]

Saito and Yamamoto, 1997
Saito, S.; Yamamoto, S., The microwave spectrum of the cyanomethyl radical CH[sub 2]CN([sup 2]B[sub 1]), J. Chem. Phys., 1997, 107, 6, 1732, https://doi.org/10.1063/1.475154 . [all data]

Ozeki, Hirao, et al., 2004
Ozeki, H.; Hirao, T.; Saito, S.; Yamamoto, S., Laboratory Microwave Spectroscopy of the Cyanomethyl Radical, CH, Astrophys. J., 2004, 684, 1, 680, https://doi.org/10.1086/425229 . [all data]

Notes

Go To: Top, Gas phase ion energetics data, Vibrational and/or electronic energy levels, References

Symbols used in this document:

EA Electron affinity
Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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