NCN

Formula: CN₂
Molecular weight: 40.0241
CAS Registry Number: 1884-64-6
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Vibrational and/or electronic energy levels

State: d

Energy (cm^-1)	Med.	Transition	λ_min (nm)	λ_max (nm)	References


T_o = 43530 ± 80	gas	d-a	250	290	Kroto, Morgan, et al., 1970
					Bise, Choi, et al., 1999

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


Σ_g⁺	1	Sym. stretch	1020	T	gas	PF	Bise, Choi, et al., 1999

State: c

Energy (cm^-1)	Med.	Transition	λ_min (nm)	λ_max (nm)	References


T_o = 38200 ± 80	gas	c-a	330	334	Kroto, 1967
					Bise, Choi, et al., 1999

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


Σ_g⁺	1	Sym. stretch	1160	T	gas	AB	Kroto, Morgan, et al., 1970

State: B

Energy (cm^-1)	Med.	Transition	λ_min (nm)	λ_max (nm)	References


T_o = 33488	gas	B-X	258	300	Kroto, Morgan, et al., 1970
					Bise, Choi, et al., 1999
T_o = 33100	Ar	B-X	240	302	Milligan, Jacox, et al., 1965
T_o = 33215	N₂	B-X	240	301	Milligan, Jacox, et al., 1965

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


Σ_g⁺	1	Sym. stretch	1050	T	gas	AB PF	Kroto, Morgan, et al., 1970 Bise, Choi, et al., 1999
	1	Sym. stretch	1050 ± 10		Ar	AB	Milligan, Jacox, et al., 1965
	1	Sym. stretch	1050 ± 10		N₂	AB	Milligan, Jacox, et al., 1965
Π_u	2	Bend	540 ± 20		gas	PF	Bise, Choi, et al., 1999

State: A

Energy (cm^-1)	Med.	Transition	λ_min (nm)	λ_max (nm)	References


T_o = 30383.967	gas	A-X	326	329	Herzberg and Travis, 1964
					Beaton, Ito, et al., 1996
					Beaton and Brown, 1997

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


Σ_g⁺	1	Sym. stretch	1254 ± 5		gas	LF	Smith, Copeland, et al., 1989
Π_u	2	Bend	534	T	gas	LF	Beaton and Brown, 1997

State: b

Energy (cm^-1)	Med.	References


T_o = 13140 ± 80	gas	Taylor, Bise, et al., 1999

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


Σ_g⁺	1	Sym. stretch	1120 ± 50	gas	PE	Taylor, Bise, et al., 1999

State: a

Energy (cm^-1)	Med.	Transition	λ_min (nm)	λ_max (nm)	References


T_o = 8150 ± 80	gas	c-a	330	334	Kroto, 1967
					Taylor, Bise, et al., 1999

State: X

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


Σ_g⁺	1	Sym. stretch	1197		Ar	IR	Milligan and Jacox, 1966
Π_u	2	Bend	437	T	gas	LF	Beaton and Brown, 1997
	2	Bend	423	m	Ar	IR	Milligan, Jacox, et al., 1965 Milligan and Jacox, 1966
Σ_u⁺	3	Asym. stretch	1466.51		gas	IR LMR	McNaughton, Metha, et al., 1995 Hensel and Brown, 1996
	3	Asym. stretch	1466.7		Ne	IR	Jacox and Thompson, 2007
	3	Asym. stretch	1475	vs	Ar	IR	Milligan, Jacox, et al., 1965 Milligan and Jacox, 1966
Σ_g⁺	3	Asym. stretch	1478	vs	N₂	IR	Milligan, Jacox, et al., 1965 Moll and Thompson, 1966 Milligan and Jacox, 1966

Additional references: Jacox, 1994, page 70; Jacox, 1998, page 180; Jacox, 2003, page 113; Devillers and Ramsay, 1971

Notes

Medium

Very strong

Tentative assignment or approximate value

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

References

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

Kroto, Morgan, et al., 1970
Kroto, H.W.; Morgan, T.F.; Sheena, H.H., Flash photolysis of cyanogen azide, NCN3, Trans. Faraday Soc., 1970, 66, 2237, https://doi.org/10.1039/tf9706602237 . [all data]

Bise, Choi, et al., 1999
Bise, R.T.; Choi, H.; Neumark, D.M., Photodissociation dynamics of the singlet and triplet states of the NCN radical, J. Chem. Phys., 1999, 111, 11, 4923, https://doi.org/10.1063/1.479751 . [all data]

Kroto, 1967
Kroto, H.W., THE, Can. J. Phys., 1967, 45, 4, 1439, https://doi.org/10.1139/p67-108 . [all data]

Milligan, Jacox, et al., 1965
Milligan, D.E.; Jacox, M.E.; Bass, A.M., Matrix Isolation Study of the Photolysis of Cyanogen Azide. The Infrared and Ultraviolet Spectra of the Free Radical NCN, J. Chem. Phys., 1965, 43, 9, 3149, https://doi.org/10.1063/1.1697289 . [all data]

Herzberg and Travis, 1964
Herzberg, G.; Travis, D.N., THE SPECTRUM AND STRUCTURE OF THE FREE NCN RADICAL, Can. J. Phys., 1964, 42, 8, 1658, https://doi.org/10.1139/p64-150 . [all data]

Beaton, Ito, et al., 1996
Beaton, S.A.; Ito, Y.; Brown, J.M., Laser Excitation Spectroscopy of theÃ3Πu--X3Σ-gTransition of the NCN Radical, J. Mol. Spectrosc., 1996, 178, 1, 99, https://doi.org/10.1006/jmsp.1996.0162 . [all data]

Beaton and Brown, 1997
Beaton, S.A.; Brown, J.M., Laser Excitation Spectroscopy of theÃ3Πu--3Σg-Transition of the NCN Radical. 2. The ν2Hot Band, J. Mol. Spectrosc., 1997, 183, 2, 347, https://doi.org/10.1006/jmsp.1997.7286 . [all data]

Smith, Copeland, et al., 1989
Smith, G.P.; Copeland, R.A.; Crosley, D.R., Electronic quenching, fluorescence lifetime, and spectroscopy of the A 3Πu state of NCN, J. Chem. Phys., 1989, 91, 4, 1987, https://doi.org/10.1063/1.457057 . [all data]

Taylor, Bise, et al., 1999
Taylor, T.R.; Bise, R.T.; Asmis, K.R.; Neumark, D.M., The singlet--triplet splittings of NCN, Chem. Phys. Lett., 1999, 301, 3-4, 413, https://doi.org/10.1016/S0009-2614(99)00053-6 . [all data]

Milligan and Jacox, 1966
Milligan, D.E.; Jacox, M.E., Matrix-Isolation Study of the Photolysis of Cyanogen Azide. II. The Symmetric Stretching Fundamental of the Free Radical NCN, J. Chem. Phys., 1966, 45, 5, 1387, https://doi.org/10.1063/1.1727771 . [all data]

McNaughton, Metha, et al., 1995
McNaughton, D.; Metha, G.F.; Tay, R., Generation of transient species by laser induced pyrolysis. The high resolution fourier transform infrared spectrum of NCN, Chem. Phys., 1995, 198, 1-2, 107, https://doi.org/10.1016/0301-0104(95)00120-D . [all data]

Hensel and Brown, 1996
Hensel, K.D.; Brown, J.M., The ν3Band of the NCN Radical, Studied by LMR, J. Mol. Spectrosc., 1996, 180, 1, 170, https://doi.org/10.1006/jmsp.1996.0238 . [all data]

Jacox and Thompson, 2007
Jacox, M.E.; Thompson, W.E., Infrared spectroscopy and photochemistry of NCCN[sup +] and CNCN[sup +] trapped in solid neon, J. Chem. Phys., 2007, 126, 5, 054308, https://doi.org/10.1063/1.2433945 . [all data]

Moll and Thompson, 1966
Moll, N.G.; Thompson, W.E., Reactions of Carbon Atoms with N2, H2, and D2 at 4.2°K, J. Chem. Phys., 1966, 44, 7, 2684, https://doi.org/10.1063/1.1727111 . [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]

Devillers and Ramsay, 1971
Devillers, C.; Ramsay, D.A., The Band System of the CCO Molecule, Can. J. Phys., 1971, 49, 22, 2839, https://doi.org/10.1139/p71-342 . [all data]

Notes

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

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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