TY - JOUR
T1 - Infrared absorption of trans-1-chloromethylallyl and trans-1-methylallyl radicals produced in photochemical reactions of trans-1,3-butadiene and Cℓ 2 in solid para-hydrogen
AU - Bahou, Mohammed
AU - Wu, Jen Yu
AU - Tanaka, Keiichi
AU - Lee, Yuan-Pern
PY - 2012/8/28
Y1 - 2012/8/28
N2 - The reactions of chlorine and hydrogen atoms with trans-1,3-butadiene in solid para-hydrogen (p-H 2) were investigated with infrared (IR) absorption spectra. When a p-H 2 matrix containing C 2 and trans-1,3-butadiene was irradiated with ultraviolet light at 365 nm, intense lines at 650.3, 809.0, 962.2, 1240.6 cm -1, and several weaker ones due to the trans-1-chloromethylallyl radical, (CH 2CHCH)CH 2Cℓ, appeared. Observed wavenumbers and relative intensities agree with the anharmonic vibrational wavenumbers and IR intensities predicted with the B3PW916-311g(2d, 2p) method. That the C atom adds primarily to the terminal carbon atom of trans-1,3-butadiene is in agreement with the path of minimum energy predicted theoretically, but in contrast to the reaction of C propene in solid p-H 2 J. Amicangelo and Y.-P. Lee, J. Phys. Chem. Lett. 1, 2956 (2010)10.1021/jz101119b in which the addition of C to the central C atom is favored, likely through steric effects in a p-H 2 matrix. A second set of lines, intense at 781.6, 957.9, 1433.6, 2968.8, 3023.5, 3107.3 cm -1, were observed when the UV-irradiated C 2trans-1,3- butadienep-H 2 matrix was further irradiated with IR light from a SiC source. These lines are assigned to the trans-1-methylallyl radical, (CH 2CHCH)CH 3, produced from reaction of 1,3-butadiene with a H atom resulted from the reaction of C atoms with solid p-H 2 exposed to IR radiation.
AB - The reactions of chlorine and hydrogen atoms with trans-1,3-butadiene in solid para-hydrogen (p-H 2) were investigated with infrared (IR) absorption spectra. When a p-H 2 matrix containing C 2 and trans-1,3-butadiene was irradiated with ultraviolet light at 365 nm, intense lines at 650.3, 809.0, 962.2, 1240.6 cm -1, and several weaker ones due to the trans-1-chloromethylallyl radical, (CH 2CHCH)CH 2Cℓ, appeared. Observed wavenumbers and relative intensities agree with the anharmonic vibrational wavenumbers and IR intensities predicted with the B3PW916-311g(2d, 2p) method. That the C atom adds primarily to the terminal carbon atom of trans-1,3-butadiene is in agreement with the path of minimum energy predicted theoretically, but in contrast to the reaction of C propene in solid p-H 2 J. Amicangelo and Y.-P. Lee, J. Phys. Chem. Lett. 1, 2956 (2010)10.1021/jz101119b in which the addition of C to the central C atom is favored, likely through steric effects in a p-H 2 matrix. A second set of lines, intense at 781.6, 957.9, 1433.6, 2968.8, 3023.5, 3107.3 cm -1, were observed when the UV-irradiated C 2trans-1,3- butadienep-H 2 matrix was further irradiated with IR light from a SiC source. These lines are assigned to the trans-1-methylallyl radical, (CH 2CHCH)CH 3, produced from reaction of 1,3-butadiene with a H atom resulted from the reaction of C atoms with solid p-H 2 exposed to IR radiation.
UR - http://www.scopus.com/inward/record.url?scp=84865791253&partnerID=8YFLogxK
U2 - 10.1063/1.4745075
DO - 10.1063/1.4745075
M3 - Article
C2 - 22938236
AN - SCOPUS:84865791253
SN - 0021-9606
VL - 137
JO - Journal of Chemical Physics
JF - Journal of Chemical Physics
IS - 8
M1 - 084310
ER -