Repozytorium

The structure, methyl rotation reflected in inelastic and quasielastic neutron scattering and vibrational spectra of 1,2,3,5-tetramethoxybenzene and its 2:1 complex with 1,2,4,5-tetracyanobenzene.

Autorzy

Andrzej Pawlukojć

M. Prager

Wanda Sawka-Dobrowolska

Grażyna Bator

Lucjan Sobczyk

A. Ivanov

S. Rois

Eugeniusz Grech

J. Nowicka-Scheibe

T. Unruh

Rok wydania

2008

Czasopismo

Journal of Chemical Physics

Numer woluminu

129

Strony

154506/1-154506/12

DOI

10.1063/1.2990650

Kolekcja

Naukowa

Język

Angielski

Typ publikacji

Artykuł

Streszczenie

X-raydiffractionstudiesshowthatmoleculesofthe1,2,3,5-tetramethoxybenzeneTMOB2·1,2,4,5-tetracyanobenzene complex form ̄CCDCCDCC ̄columns with the shortdistances between molecular planes of C and D molecules equal to 3.186 Å. The vibrational spectrarecorded by using the inelastic neutron scattering, Raman, IR, and quasielastic neutron scatteringQENStechniques aided by density functional theory calculations for the isolated molecules andthe crystalline state enabled all four inequivalent librational modes, ascribed to the methoxy groups,to be analyzed. A rather good consistency was found between the experimental frequencies andthose calculated for the crystal. The consistency was also achieved between the experimentalstructure of molecules and the theoretically reproduced one. A close similarity of the structures ofthe TMOB molecule isolated and in the complex is taken as a sign of dominating intramolecularinteraction. The QENS spectra contain three Lorentzians of relative intensities of 1:1:2. Thus thetwo most strongly hindered of the four inequivalent methoxy groups in the crystalline lattice arecharacterized by rather similar barrier heights in good agreement with the packing analysis.

Adres publiczny

https://doi.org/10.1063/1.2990650

Strona internetowa wydawcy

https://www.aip.org/

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