Cyanomethylene

Formula: C₂HN
Molecular weight: 39.0360
IUPAC Standard InChI: InChI=1S/C2HN/c1-2-3/h1H
IUPAC Standard InChIKey: SZICEGNEOSKVLO-UHFFFAOYSA-N
CAS Registry Number: 2612-62-6
Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript.
Other names: HCCN radical
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Information on this page:
Other data available:
- Reaction thermochemistry data
Data at other public NIST sites:
- Gas Phase Kinetics Database
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Gas phase ion energetics data

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

View reactions leading to C₂HN⁺ (ion structure unspecified)

Electron affinity determinations

EA (eV)	Method	Reference	Comment
2.003 ± 0.014	LPES	Nimlos, Davico, et al., 2002
1.883 ± 0.013	LPES	Nimlos, Davico, et al., 2002
2.01 ± 0.34	D-EA	Matimba, Crabbendam, et al., 1992
1.93 ± 0.34	D-EA	Grabowski and Melly, 1987	Between H₂O₂ and mCl-toluene
0.80 ± 0.40	EIAE	Heni and Illenberger, 1986	From MeCN
>1.09997	EIAE	Tsuda, Yokohata, et al., 1971	From MeCN. G3MP2B3 calculations indicate an EA of ca. 2.0 eV.

Vibrational and/or electronic energy levels

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

Data compiled by: Marilyn E. Jacox

State: ?

Med.	λ_min (nm)	λ_max (nm)	References


Ar	240	340	Dendramis and Leroi, 1977

State: a

Energy (cm^-1)	Med.	References


T_o = 4115 ± 120	gas	Nimlos, Davico, et al., 2002, 2
		Vogelhuber, Wren, et al., 2011

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


2	CN stretch	1936 ± 40	gas	PE	Vogelhuber, Wren, et al., 2011

State: X

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


Σ⁺	1	CH stretch	3246.66		gas	CC	Morter, Farhat, et al., 1993
	1	CH stretch	3229.4	s	Ar	IR	Dendramis and Leroi, 1977 Maier, Reisenauer, et al., 1998
	1	CH stretch	3213.3		N₂	IR	Maier, Reisenauer, et al., 1998
	2	CCN a-stretch	1734.9	s	Ar	IR	Dendramis and Leroi, 1977 Maier, Reisenauer, et al., 1998
	2	CCN a-stretch	1750.3		N₂	IR	Maier, Reisenauer, et al., 1998
	3	CCN s-stretch	1178.6	w m	Ar	IR	Dendramis and Leroi, 1977 Maier, Reisenauer, et al., 1998
Π	4	H deform.	383 ± 20		gas	CC MW	Morter, Farhat, et al., 1993 McCarthy, Gottlieb, et al., 1995
	5	Skel. deform.	128.91		gas	MW CC	McCarthy, Gottlieb, et al., 1995 Han, Hung, et al., 1999 Allen, Evenson, et al., 2001 Nimlos, Davico, et al., 2002, 2

Additional references: Jacox, 1994, page 156; Jacox, 1998, page 234; Jacox, 2003, page 185; Bernheim, Kempf, et al., 1965; Merer and Travis, 1965; Merer and Travis, 1966; Saito, Endo, et al., 1984; Brown, Saito, et al., 1990; Endo and Ohshima, 1993; Sun, Kosterev, et al., 1998; Jones, Sun, et al., 2001; Hung, Sun, et al., 2001

Notes

Weak

Medium

Strong

Energy separation between the v = 0 levels of the excited and electronic ground states.

References

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

Nimlos, Davico, et al., 2002
Nimlos, M.R.; Davico, G.; Geise, C.M.; Wenthold, P.G.; Lineberger, W.C.; Blanksby, S.J.; Hadad, C.M.; Petersso, Photoelectron spectroscopy of HCCN- and HCNC- reveals the quasilinear triplet carbenes, HCCN and HCNC, J. Chem. Phys., 2002, 117, 9, 4323-4339, https://doi.org/10.1063/1.1496473 . [all data]

Matimba, Crabbendam, et al., 1992
Matimba, H.E.K.; Crabbendam, A.M.; Ingemann, S.; Nibbering, N.M.M., Gas-phase Bimolecular Chemistry of the .-CHNC and .-CHCN Radical Anions, Int. J. Mass Spectrom. Ion Proc., 1992, 114, 1-2, 85, https://doi.org/10.1016/0168-1176(92)85024-T . [all data]

Grabowski and Melly, 1987
Grabowski, J.J.; Melly, S.J., Formation of carbene radical anions: Gas phase reaction of the atomic oxygen anion with organic neutrals, Int. J. Mass Spectrom. Ion Processes, 1987, 81, 147. [all data]

Heni and Illenberger, 1986
Heni, M.; Illenberger, E., Electron attachment by saturated nitriles. Acrylonitrile (CH₂H₃CN), and benzonitrile (C₆H₅CN), Int. J. Mass Spectrom. Ion Phys., 1986, 73, 127. [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]

Dendramis and Leroi, 1977
Dendramis, A.; Leroi, G.E., Matrix isolation spectroscopic study of the free radical HCCN, J. Chem. Phys., 1977, 66, 10, 4334, https://doi.org/10.1063/1.433724 . [all data]

Nimlos, Davico, et al., 2002, 2
Nimlos, M.R.; Davico, G.; Geise, C.M.; Wenthold, P.G.; Blanksby, W.C. Lineberger.S.J.; Hadad, C.M.; Petersson, G.A.; Ellison, G.B., Photoelectron spectroscopy of HCCN[sup -] and HCNC[sup -] reveals the quasilinear triplet carbenes, HCCN and HCNC, J. Chem. Phys., 2002, 117, 9, 4323, https://doi.org/10.1063/1.1496473 . [all data]

Vogelhuber, Wren, et al., 2011
Vogelhuber, K.M.; Wren, S.W.; Shaffer, C.J.; McMahon, R.J.; McCoy, A.B.; Lineberger, W.C., Photoelectron spectroscopy of HC4N-, J. Chem. Phys., 2011, 135, 20, 204307, https://doi.org/10.1063/1.3663617 . [all data]

Morter, Farhat, et al., 1993
Morter, C.L.; Farhat, S.K.; Curl, R.F., The ν1 fundamental of HCCN: evidence for quasilinearity, Chem. Phys. Lett., 1993, 207, 2-3, 153, https://doi.org/10.1016/0009-2614(93)87007-P . [all data]

Maier, Reisenauer, et al., 1998
Maier, G.; Reisenauer, H.P.; Rademacher, K., Cyanocarbene, Isocyanocarbene, and Azacyclopropenylidene: A Matrix-Spectroscopic Study, Chem. Eur. J., 1998, 4, 10, 1957, https://doi.org/10.1002/(SICI)1521-3765(19981002)4:10<1957::AID-CHEM1957>3.0.CO;2-1 . [all data]

McCarthy, Gottlieb, et al., 1995
McCarthy, M.C.; Gottlieb, C.A.; Cooksy, A.L.; Thaddeus, P., Evidence for nonrigid HCCN, J. Chem. Phys., 1995, 103, 18, 7779, https://doi.org/10.1063/1.470193 . [all data]

Han, Hung, et al., 1999
Han, J.-X.; Hung, P.Y.; DeSain, J.; Jones, W.E.; Curl, R.F., The ν1 + ν5 Band of HCCN: Determination of the ν5 Vibrational Energy, J. Mol. Spectrosc., 1999, 198, 2, 421, https://doi.org/10.1006/jmsp.1999.7965 . [all data]

Allen, Evenson, et al., 2001
Allen, M.D.; Evenson, K.M.; Brown, J.M., High-Resolution Spectroscopic Measurements of the ν5 Bending Vibration--Rotation Band of HCCN in its X3Σ- State at 129 cm-1, J. Mol. Spectrosc., 2001, 209, 2, 143, https://doi.org/10.1006/jmsp.2001.8387 . [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]

Bernheim, Kempf, et al., 1965
Bernheim, R.A.; Kempf, R.J.; Gramas, J.V.; Skell, P.S., Electron Paramagnetic Resonance of Triplet Alternant Methylenes. Propargylene and Homologs, J. Chem. Phys., 1965, 43, 1, 196, https://doi.org/10.1063/1.1696454 . [all data]

Merer and Travis, 1965
Merer, A.J.; Travis, D.N., ABSORPTION SPECTRUM OF THE CCN RADICAL, Can. J. Phys., 1965, 43, 10, 1795, https://doi.org/10.1139/p65-173 . [all data]

Merer and Travis, 1966
Merer, A.J.; Travis, D.N., THE ABSORPTION SPECTRUM OF CNC, Can. J. Phys., 1966, 44, 2, 353, https://doi.org/10.1139/p66-029 . [all data]

Saito, Endo, et al., 1984
Saito, S.; Endo, Y.; Hirota, E., The microwave spectrum of a triplet carbene: HCCN in the X 3Σ- state, J. Chem. Phys., 1984, 80, 4, 1427, https://doi.org/10.1063/1.446879 . [all data]

Brown, Saito, et al., 1990
Brown, F.X.; Saito, S.; Yamamoto, S., Microwave spectroscopy of isotopically substituted HCCN and its molecular structure, J. Mol. Spectrosc., 1990, 143, 2, 203, https://doi.org/10.1016/0022-2852(91)90084-N . [all data]

Endo and Ohshima, 1993
Endo, Y.; Ohshima, Y., Fourier-transform microwave spectroscopy of the HCCN radical. Determination of the hyperfine coupling constants, J. Chem. Phys., 1993, 98, 9, 6618, https://doi.org/10.1063/1.464804 . [all data]

Sun, Kosterev, et al., 1998
Sun, F.; Kosterev, A.; Scott, G.; Litosh, V.; Curl, R.F., ν[sub 1] and ν[sub 1]+ν[sub 5] of DCCN: Determination of the ν[sub 5] energy and the quasilinearity of DCCN, J. Chem. Phys., 1998, 109, 20, 8851, https://doi.org/10.1063/1.477556 . [all data]

Jones, Sun, et al., 2001
Jones, W.E.; Sun, F.; Curl, R.F.; Allen, M.D.; Evenson, K.M.; Brown, J.M., Can. J. Phys., 2001, 79, 389. [all data]

Hung, Sun, et al., 2001
Hung, P.Y.; Sun, F.; Hunt, N.T.; Burns, L.A.; Curl, R.F., High-resolution infrared spectroscopic determination of the nν[sub 5][sup ±n] vibrational energies of HCCN and DCCN, J. Chem. Phys., 2001, 115, 20, 9331, https://doi.org/10.1063/1.1413981 . [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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