Fast Stochastic Reorientations in Nematic PAA and PAP |
| R. Podsiadłya, J. Mayerb, J.A. Janikb, J. Krawczykb and T. Staneka aFaculty of Chemistry of the Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland bH. Niewodniczański Institute of Nuclear Physics, Radzikowskiego 152, 31-342 Kraków, Poland |
| Received: October 22, 1996; revised version: January 3, 1997 |
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| Incoherent quasielastic neutron scattering spectra were measured for nematic para-azoxyanisole (PAA) and para-azoxyphenetole (PAP) with the energy resolution of ca. 30 μ eV, at Dubna IBR-2 reactor. Data processing contained a careful background subtraction and the multiple scattering correction. The corrected spectra were subjected to a reorientational model fitting procedure. For PAA, a model of two convoluted reorientations - that of benzene rings coupled with the terminals and that of the whole molecule around the long molecular axis - gave a fairly good description of the quasielastic neutron scattering spectrum. For PAP, introducing a third motion - interconformational jumps in the ethoxy terminals - in addition to motions suggested for PAA, gave a good agreement with the measured quasielastic neutron scattering spectrum. |
| DOI: 10.12693/APhysPolA.91.513 PACS numbers: 24.50.Fq, 35.20.Yh, 61.30.Eb |