TY  - JOUR
A1  - Schweiss, Bernd Peter
A1  - Fueß, Hartmut
A1  - Fecher, Gerhard
A1  - Weiss, Alarich
T1  - On the order-disorder phase transformation of anilinium halides. V. Inelastic neutron scattering on anilinium bromide, C6H₅ND3⊕ Br⊖, and its partially deuterated derivatives C₆H₅ND₃⊕Br⊖ and C6D5NH3⊕Br⊖
T2  - Zeitschrift für Naturforschung, A
N2  - The order-disorder phase transition which occurs at Tc = 296.9 K in anilinium bromide, C6H5NH3Br, is studied by inelastic neutron time-of-flight measurements. Data are taken from hydrogenated and partially deuterated samples (C6D5NH3Br and C6H5ND3Br) below and above the transition temperature. From the inelastic scattering data the phonon frequency distribution in the range of the intermolecular vibrations is calculated. The assignment of bands is given and changes in the spectra with temperature are discussed. The analysis of the quasielastic line revealed substantial broadening due to rotational diffusion of the -NH3⊕ group. These jump diffusion processes were observed in the orthorhombic high temperature and - with markedly diminished rate - in the monoclinic phase below Tc. From the correlation times at different temperatures the activation energies are estimated for both phases. Comparison with calculated elastic incoherent structure factors suggests jumps of 60° for hindered rotation.
Y1  - 2014
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/74300
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-743007
SN  - 1865-7109
VL  - 38
IS  - 3
SP  - 350
EP  - 358
PB  - Verlag der Zeitschrift für Naturforschung
CY  - Tübingen
ER  -