NMR Study of Phase Transitions in New Ferroelectric Crystal—(C5H5NH)5Bi2Br11

Structural characterization, thermal, dielectric, vibrational properties and molecular dynamics of (C5H5NH)3BiCl6

“…In our paper devoted to (C 5 H 5 NH) 5 Bi 2 Br 11 [37] a similar symmetric minimum was observed, however, at the markedly lower helium temperatures. Moreover, the T 1 min value, equal to 0.84 s, was close to that presented in this paper.…”

Dynamics of Molecular Crystals by Means of 1H NMR Relaxometry: Dynamical Heterogeneity versus Homogenous Motion

“…possessing different chemical surroundings) pyridinium cations. The compound undergoes two phase transitions: from phase III (ferroelectric) to phase II (paraelectric) at 118 K and from phase II to phase I (ferroelastic) at 405 K . The structure of the pyridinium cation is shown in Figure a, whereas the structure of the unit cell of the crystal is shown in Figure b .…”

“…On the other hand, accepting such an assumption for nonamorphous solids is definitely not straightforward. Besides playing the role of a model system, the compound shows interesting para‐ and ferroelectric properties . Halogenobismuthates(III) and halogenoantimonates(III) containing organic amines in their structure belong to the class of organic–inorganic hybrid materials.…”

Temperature dependence of nonequivalent potential wells for pyridinium ion reorientation in pyridinium tetrachloroiodate(III), PyHICl4, studied by 1H14N nuclear quadrupole double resonance

“…In the ferroelectric phase, the small-angle librations of the pyridinium ion explain the NMR data, while above T c , the presence of two different dynamical nonequivalent pyridinium cations in (C 5 H 5 NH) 5 Bi 2 Br 11 may be accepted. The order-disorder phase transition of pyridinium tetrachloroiodate(III), PyHICl 4 , was previously studied by single-crystal X-ray analysis and dielectric and heat capacity measurements.…”

“…A 1 H NMR study of the phase transitions in (C 6 H 5 NH) 5 Bi 2 Br 11 [5] has been used to elucidate the pyridinium dynamics in ferroelectric as well as in the paraelectric phases. In the ferroelectric phase, the small-angle librations of the pyridinium ion explain the NMR data, while above T c , the presence of two different dynamical nonequivalent pyridinium cations in (C 5 H 5 NH) 5 Bi 2 Br 11 may be accepted.…”