2-Methylallyl radical

Formula: C₄H₇
Molecular weight: 55.0984
IUPAC Standard InChI: InChI=1S/C4H7/c1-4(2)3/h1-2H2,3H3
IUPAC Standard InChIKey: LJXPWUAAAAXJBX-UHFFFAOYSA-N
CAS Registry Number: 15157-95-6
Chemical structure:
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Vibrational and/or electronic energy levels

State: ?

Med.	λ_min (nm)	λ_max (nm)	References


gas	223	242	Callear and Lee, 1968
			Nakashima and Yoshihara, 1987
			Chen, Wu, et al., 2003

State: E

Energy (cm^-1)	Med.	References


T_o = 38774	gas	Callear and Lee, 1968
		Hudgens and Dulcey, 1985
		Nakashima and Yoshihara, 1987
		Chen, Wu, et al., 2003

No.	cm^-1	Med.	Method	References


11	1362	gas	MPI	Chen, Wu, et al., 2003
13	1040	gas	MPI	Chen, Wu, et al., 2003
15	935	gas	MPI	Chen, Wu, et al., 2003
16	848	gas	MPI	Chen, Wu, et al., 2003
17	468	gas	AB MPI	Callear and Lee, 1968 Nakashima and Yoshihara, 1987 Chen, Wu, et al., 2003
18	401	gas	AB MPI	Callear and Lee, 1968 Hudgens and Dulcey, 1985 Nakashima and Yoshihara, 1987 Chen, Wu, et al., 2003

State: C

Energy (cm^-1)	Med.	References


T_o = 38957	gas	Callear and Lee, 1968
		Nakashima and Yoshihara, 1987
		Chen, Wu, et al., 2003

No.	cm^-1	Med.	Method	References


8	1517	gas	MPI	Chen, Wu, et al., 2003
11	1349	gas	MPI	Chen, Wu, et al., 2003
13	1056	gas	MPI	Chen, Wu, et al., 2003
15	967	gas	MPI	Chen, Wu, et al., 2003
16	898	gas	MPI	Chen, Wu, et al., 2003
17	467	gas	MPI	Chen, Wu, et al., 2003
18	381	gas	MPI	Chen, Wu, et al., 2003

State: B

Energy (cm^-1)	Med.	References


T_o = 38337	gas	Hudgens and Dulcey, 1985
		Chen, Wu, et al., 2003

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


a₁	8		1431	gas	MPI	Chen, Wu, et al., 2003
	11		1370	gas	MPI	Chen, Wu, et al., 2003
	13		1013	gas	MPI	Chen, Wu, et al., 2003
	15		947	gas	MPI	Chen, Wu, et al., 2003
	17	C₃ deformation	444	gas	MPI	Hudgens and Dulcey, 1985 Chen, Wu, et al., 2003
	18		370	gas	MPI	Chen, Wu, et al., 2003

State: X

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


		CH₂ stretch	3109		N₂	IR	Gusel'nikov, Zimmermann, et al., 1985 Avakyan, Volkova, et al., 1986
		CH₂ stretch	3025		N₂	IR	Gusel'nikov, Zimmermann, et al., 1985 Avakyan, Volkova, et al., 1986
			1000		N₂	IR	Gusel'nikov, Zimmermann, et al., 1985 Avakyan, Volkova, et al., 1986
			475		N₂	IR	Gusel'nikov, Zimmermann, et al., 1985 Avakyan, Volkova, et al., 1986
a'	5	CH₂ scissors	1492 ± 4		gas	Ra	Getty, Liu, et al., 1996
	5	CH₂ scissors	1498		N₂	IR	Gusel'nikov, Zimmermann, et al., 1985 Avakyan, Volkova, et al., 1986
	7	CH₃ s-deform.	1392 ± 4		gas	Ra	Getty, Liu, et al., 1996
	7	CH₃ s-deform.	1394		N₂	IR	Gusel'nikov, Zimmermann, et al., 1985 Avakyan, Volkova, et al., 1986
	8	CH₂ rock	1353 ± 4		gas	Ra	Getty, Liu, et al., 1996
	9	C₃ stretch	1037 ± 4		gas	Ra PE	Getty, Liu, et al., 1996 Wenthold, Polak, et al., 1996
	11	C-CH₃ stretch	865 ± 4		gas	Ra	Getty, Liu, et al., 1996
	12	CCH₂ OPLA	780 ± 10	H	gas	PE	Wenthold, Polak, et al., 1996
	12	CCH₂ OPLA	795		N₂	IR	Gusel'nikov, Zimmermann, et al., 1985 Avakyan, Volkova, et al., 1986
	14	CH₂ twist	538	H T	gas	Ra	Getty, Liu, et al., 1996
	15	C₃ deformation	432 ± 4		gas	Ra PE	Getty, Liu, et al., 1996 Wenthold, Polak, et al., 1996
	15	C₃ deformation	432 ± 4		gas	MPI	Chen, Wu, et al., 2003
a	19	CH₂ scissors	1471		N₂	IR	Gusel'nikov, Zimmermann, et al., 1985 Avakyan, Volkova, et al., 1986
	20	CH₃ deformation	1400		N₂	IR	Gusel'nikov, Zimmermann, et al., 1985 Avakyan, Volkova, et al., 1986

Additional references: Jacox, 1998, page 343

Notes

(1/2)(2ν)

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

Callear and Lee, 1968
Callear, A.B.; Lee, H.K., Electronic spectra of the free allyl radical and some of its simple derivatives, Trans. Faraday Soc., 1968, 64, 308, https://doi.org/10.1039/tf9686400308 . [all data]

Nakashima and Yoshihara, 1987
Nakashima, N.; Yoshihara, K., Oscillator Strengths of the Ultraviolet Bands of Hot and Relaxed Methallyl, Allyl, and Methyl Radicals, Laser Chem., 1987, 7, 2-4, 177, https://doi.org/10.1155/LC.7.177 . [all data]

Chen, Wu, et al., 2003
Chen, C.-C.; Wu, H.-C.; Tseng, C.-M.; Yang, Y.-H.; Chen, Y.-T., One- and two-photon excitation vibronic spectra of 2-methylallyl radical at 4.6--5.6 eV, J. Chem. Phys., 2003, 119, 1, 241, https://doi.org/10.1063/1.1576381 . [all data]

Hudgens and Dulcey, 1985
Hudgens, J.W.; Dulcey, C.S., Observation of the 3s 2A1 Rydberg states of allyl and 2-methylallyl radicals with multiphoton ionization spectroscopy, J. Phys. Chem., 1985, 89, 8, 1505, https://doi.org/10.1021/j100254a039 . [all data]

Gusel'nikov, Zimmermann, et al., 1985
Gusel'nikov, L.E.; Zimmermann, G.; Ziegler, U., et al., Dokl. Akad. Nauk SSSR, 1985, 282, 1416. [all data]

Avakyan, Volkova, et al., 1986
Avakyan, V.G.; Volkova, V.V.; Gusel'nikov, L.E.; Ziegler, U.; Zimmermann, G., et al., Dokl. Akad. Nauk SSSR, 1986, 290, 1133. [all data]

Getty, Liu, et al., 1996
Getty, J.D.; Liu, X.; Kelly, P.B., Observation of the β-methylallyl radical by resonance Raman spectroscopy, J. Chem. Phys., 1996, 104, 9, 3176, https://doi.org/10.1063/1.471082 . [all data]

Wenthold, Polak, et al., 1996
Wenthold, P.G.; Polak, M.L.; Lineberger, W.C., Photoelectron Spectroscopy of the Allyl and 2-Methylallyl Anions, J. Phys. Chem., 1996, 100, 17, 6920, https://doi.org/10.1021/jp953401n . [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]

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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