TY - JOUR

T1 - Thermal self polymerization investigated by microwave molecular spectroscopy

T2 - Rotational characterization of the methyl methacrylate dimer

AU - Herbers, Sven

AU - Obenchain, Daniel A.

AU - Lengsfeld, Kevin G.

AU - Kuper, Henning

AU - Becker, Jörg A.

AU - Grabow, Jens Uwe

N1 - Funding Information: We want to acknowledge the financial support of the Land Niedersachsen , the Deutsche Forschungsgemeinschaft (DFG), the Alexander von Humboldt Foundation and the support of the technical shops of the Institut für Physikalische Chemie and of the cluster system team at the Leibniz University IT services (LUIS) of Hannover, Germany in the course of this work. Publisher Copyright: © 2018 Elsevier Inc. Copyright: Copyright 2018 Elsevier B.V., All rights reserved.

PY - 2018/9

Y1 - 2018/9

N2 - Rotational constants, Watson's S centrifugal distortion coefficients, and internal rotation parameters of the methyl methacrylate dimer were retrieved from the microwave spectrum of the dimer phase of methyl methacrylate, which was subjected to a thermal self-polymerization process. The dimer contains three methyl rotors. Coupling of the methyl internal rotation to the overall rotation causes a complicated splitting of the rotational spectrum. The fact that only the two methoxymethyl groups contributed resolvable (>5kHz) splittings simplified the spectral assignment somewhat and a fit of spectroscopic parameters to the experimental data was achieved to within experimental accuracy. The methyl methacrylate self-polymerization system is intended as an easily accessible model system for polymerization and the analysis of the dimer presented in this study contributes to the stepwise understanding by means of microwave spectroscopy and ab initio methods.

AB - Rotational constants, Watson's S centrifugal distortion coefficients, and internal rotation parameters of the methyl methacrylate dimer were retrieved from the microwave spectrum of the dimer phase of methyl methacrylate, which was subjected to a thermal self-polymerization process. The dimer contains three methyl rotors. Coupling of the methyl internal rotation to the overall rotation causes a complicated splitting of the rotational spectrum. The fact that only the two methoxymethyl groups contributed resolvable (>5kHz) splittings simplified the spectral assignment somewhat and a fit of spectroscopic parameters to the experimental data was achieved to within experimental accuracy. The methyl methacrylate self-polymerization system is intended as an easily accessible model system for polymerization and the analysis of the dimer presented in this study contributes to the stepwise understanding by means of microwave spectroscopy and ab initio methods.

KW - Dimer

KW - Fourier transform microwave spectroscopy

KW - Large amplitude motion

KW - Methyl methacrylate

KW - Rotational spectrum

KW - Thermal self polymerization

UR - http://www.scopus.com/inward/record.url?scp=85050510758&partnerID=8YFLogxK

U2 - 10.1016/j.jms.2018.07.007

DO - 10.1016/j.jms.2018.07.007

M3 - Article

AN - SCOPUS:85050510758

VL - 351

SP - 49

EP - 54

JO - Journal of molecular spectroscopy

JF - Journal of molecular spectroscopy

SN - 0022-2852

ER -