Benzyne

Formula: C₆H₄
Molecular weight: 76.0960
IUPAC Standard InChI: InChI=1S/C6H4/c1-2-4-6-5-3-1/h1-4H
IUPAC Standard InChIKey: KLYCPFXDDDMZNQ-UHFFFAOYSA-N
CAS Registry Number: 462-80-6
Chemical structure:
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Vibrational and/or electronic energy levels

State: ?

Energy (cm^-1)	Med.	References


T_x = 50200	Ar	Munzel and Schweig, 1988
		Simon, Munzel, et al., 1990

State: ?

Energy (cm^-1)	Med.	References


T_x = 40600	Ar	Munzel and Schweig, 1988
		Simon, Munzel, et al., 1990

State: ?

Energy (cm^-1)	Med.	References


T_x = 28730	Ne	Radziszewski, Hess, et al., 1992

State: ?

Energy (cm^-1)	Med.	References


T_x = 26300	Ar	Munzel and Schweig, 1988

State: a

Energy (cm^-1)	Med.	References


T_o = 13140 ± 50	gas	Leopold, Stevens-Miller, et al., 1986
		Wenthold, Squires, et al., 1998

Vib. sym.	cm^-1	Med.	Method	References


a₁	1520 ± 40	gas	PE	Wenthold, Squires, et al., 1998
	1395 ± 30	gas	PE	Leopold, Stevens-Miller, et al., 1986 Wenthold, Squires, et al., 1998
	1275 ± 30	gas	PE	Wenthold, Squires, et al., 1998
	560 ± 20	gas	PE	Leopold, Stevens-Miller, et al., 1986 Wenthold, Squires, et al., 1998

State: X

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


a₁	1	CH stretch	3094	w m	Ne	IR	Radziszewski, Hess, et al., 1992
	1	CH stretch	3088		N₂	IR	Dunkin and MacDonald, 1979
	2	CH stretch	3071	w	Ne	IR	Radziszewski, Hess, et al., 1992
	3	CC stretch	1860 ± 15		gas	PE	Leopold, Stevens-Miller, et al., 1986 Wenthold, Squires, et al., 1998
	3	CC stretch	1846	w	Ne	IR	Radziszewski, Hess, et al., 1992
	4	Mixed	1415	w	Ne	IR	Radziszewski, Hess, et al., 1992
	5	Mixed	1271	w	Ne	IR	Radziszewski, Hess, et al., 1992
	6	CH deform.	1055	w m	Ne	IR	Radziszewski, Hess, et al., 1992
	6	CH deform.	1053	m	Ar	IR	Chapman, Mattes, et al., 1973
	6	CH deform.	1056		N₂	IR	Dunkin and MacDonald, 1979 Nam and Leroi, 1987
	7	Ring stretch	1010 ± 40		gas	PE	Leopold, Stevens-Miller, et al., 1986 Wenthold, Squires, et al., 1998
	7	Ring stretch	1039	m	Ne	IR	Radziszewski, Hess, et al., 1992
	7	Ring stretch	1038	m	Ar	IR	Chapman, Mattes, et al., 1973
	7	Ring stretch	1039		N₂	IR	Dunkin and MacDonald, 1979 Nam and Leroi, 1987
	8	Ring stretch	982	w m	Ne	IR	Radziszewski, Hess, et al., 1992
	9	Ring deform.	600 ± 15		gas	PE	Leopold, Stevens-Miller, et al., 1986 Wenthold, Squires, et al., 1998
	9	Ring deform.	589	w	Ne	IR	Radziszewski, Hess, et al., 1992
b₁	14	CH wag	838	w	Ne	IR	Radziszewski, Hess, et al., 1992
	15	CH wag	737	s	Ne	IR	Radziszewski, Hess, et al., 1992
	15	CH wag	736	vs	Ar	IR	Chapman, Mattes, et al., 1973
	15	CH wag	743		N₂	IR	Dunkin and MacDonald, 1979 Nam and Leroi, 1987
	16	Ring torsion	388	w m	Ne	IR	Radziszewski, Hess, et al., 1992
b₂	17	CH stretch	3086	m	Ne	IR	Radziszewski, Hess, et al., 1992
	18	CH stretch	3049	w	Ne	IR	Radziszewski, Hess, et al., 1992
	19	Ring stretch	1451	m	Ne	IR	Radziszewski, Hess, et al., 1992
	19	Ring stretch	1451	m	Ar	IR	Chapman, Mattes, et al., 1973
	19	Ring stretch	1448		N₂	IR	Dunkin and MacDonald, 1979 Nam and Leroi, 1987
	20	Mixed	1394	w m	Ne	IR	Radziszewski, Hess, et al., 1992
	20	Mixed	1395		N₂	IR	Nam and Leroi, 1987
	20	Mixed	1355		N₂	IR	Nam and Leroi, 1987
	21	Mixed	1307	w	Ne	IR	Radziszewski, Hess, et al., 1992
	22	Mixed	1094	w	Ne	IR	Radziszewski, Hess, et al., 1992
	23	Ring deform.	849	m s	Ne	IR	Radziszewski, Hess, et al., 1992
	23	Ring deform.	849	s	Ar	IR	Chapman, Mattes, et al., 1973
	23	Ring deform.	847		N₂	IR	Dunkin and MacDonald, 1979 Nam and Leroi, 1987
	24	Ring deform.	472	vs	Ne	IR	Radziszewski, Hess, et al., 1992
	24	Ring deform.	469	vs	Ar	IR	Chapman, Mattes, et al., 1973
	24	Ring deform.	472		N₂	IR	Dunkin and MacDonald, 1979 Nam and Leroi, 1987

Additional references: Jacox, 1994, page 386; Jacox, 2003, page 364; Brown, Godfrey, et al., 1986; Robertson, Godfrey, et al., 2003; Kukolich, Tanjaroon, et al., 2003; Kukolich, McCarthy, et al., 2004

Notes

Weak

Medium

Strong

Very strong

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

Energy separation between the band maximum of the excited electronic state and the v = 0 level of the ground state.

References

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

Munzel and Schweig, 1988
Munzel, N.; Schweig, A., UV/VIS absorption spectrum, geometry and electronic structure of transient o-benzyne, Chem. Phys. Lett., 1988, 147, 2-3, 192, https://doi.org/10.1016/0009-2614(88)85082-6 . [all data]

Simon, Munzel, et al., 1990
Simon, J.G.G.; Munzel, N.; Schweig, A., Matrix isolation photochemistry: photoequilibrium between transient o-benzyne, carbon monoxide and transient cyclopentadienylideneketene in an argon matrix, Chem. Phys. Lett., 1990, 170, 2-3, 187, https://doi.org/10.1016/0009-2614(90)87113-6 . [all data]

Radziszewski, Hess, et al., 1992
Radziszewski, J.G.; Hess, B.A., Jr.; Zahradnik, R., Infrared spectrum of o-benzyne: experiment and theory, J. Am. Chem. Soc., 1992, 114, 1, 52, https://doi.org/10.1021/ja00027a007 . [all data]

Leopold, Stevens-Miller, et al., 1986
Leopold, D.G.; Stevens-Miller, A.E.; Linebergr, W.C., Determination of the singlet-triplet splitting and electron affinity of o-benzyne by negative ion photoelectron spectroscopy, J. Am. Chem. Soc., 1986, 108, 7, 1379, https://doi.org/10.1021/ja00267a003 . [all data]

Wenthold, Squires, et al., 1998
Wenthold, P.G.; Squires, R.R.; Lineberger, W.C., Ultraviolet Photoelectron Spectroscopy of the, J. Am. Chem. Soc., 1998, 120, 21, 5279, https://doi.org/10.1021/ja9803355 . [all data]

Dunkin and MacDonald, 1979
Dunkin, I.R.; MacDonald, J.G., J. Chem. Soc., 1979, Chem. Commun. 772. [all data]

Chapman, Mattes, et al., 1973
Chapman, O.L.; Mattes, K.; McIntosh, C.L.; Pacansky, J.; Calder, G.V.; Orr, G., Photochemical transformations. LII. Benzyne, J. Am. Chem. Soc., 1973, 95, 18, 6134, https://doi.org/10.1021/ja00799a060 . [all data]

Nam and Leroi, 1987
Nam, H.-H.; Leroi, G.E., On the vibrational spectrum of matrix isolated o-benzyne, J. Mol. Struct., 1987, 157, 1-3, 301, https://doi.org/10.1016/0022-2860(87)87100-4 . [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, 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]

Brown, Godfrey, et al., 1986
Brown, R.D.; Godfrey, P.D.; Rodler, M., Microwave spectrum of benzyne, J. Am. Chem. Soc., 1986, 108, 6, 1296, https://doi.org/10.1021/ja00266a028 . [all data]

Robertson, Godfrey, et al., 2003
Robertson, E.G.; Godfrey, P.D.; McNaughton, D., The microwave spectrum of o-benzyne measured in a novel Stark modulated spectrometer for transient molecules, J. Mol. Spectrosc., 2003, 217, 1, 123, https://doi.org/10.1016/S0022-2852(02)00021-8 . [all data]

Kukolich, Tanjaroon, et al., 2003
Kukolich, S.G.; Tanjaroon, C.; McCarthy, M.C.; Thaddeus, P., Microwave spectrum of o-benzyne produced in a discharge nozzle, J. Chem. Phys., 2003, 119, 8, 4353, https://doi.org/10.1063/1.1593015 . [all data]

Kukolich, McCarthy, et al., 2004
Kukolich, S.G.; McCarthy, M.C.; Thaddeus, P., Molecular Structure of, J. Phys. Chem. A, 2004, 108, 14, 2645, https://doi.org/10.1021/jp031344p . [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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