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Item Determination of Landau free-energy parameters by dielectric measurements in the ferroelectric TSCC(1981-05) Bornarel, J.; Schmidt, V. HugoThe authors measured the adiabatic dielectric permittivity epsilon b of tris-sarcosine calcium chloride (TSCC) at 400 Hz near the ferroelectric transition for DC bias fields up to 5000 V cm-1. They found epsilon infinity =4.2+or-0.2, Curie-Weiss constant C+=38.3+or-0.3K, T0=129.4+or-0.1K, and Landau coefficients A=(2.95+or-0.2)*109 V m A-1 s-1 K-1 and B=(3.5+or-0.1)*1015 V m5 A-3 s-3. They observed evidence of an internal bias field as reported previously by others.Item Anomalies of hypersound velocity and attenuation in ferroelectric tris-sarcosine calcium chloride (TSCC) for small-angle and right-angle Brillouinscattering and Brillouin backscattering(1986-07) Wang, J. T.; Schmidt, V. HugoThe Brillouin spectra of ferroelectric tris-sarcosine calcium chloride have been observed using small-angle and right-angle scattering and also backscattering. For different-frequency phonons along the same direction, analogous anomalies in the sound velocity and the attenuation are seen. The smallest angle we have achieved is 7.48°. The temperature and frequency dependences of the sound velocity are discussed. The fact that the linewidth maximum for [001] phonons occurs somewhat below Tc seems to indicate that the anomalies are due to piezoelectric coupling induced by spontaneous polarization below Tc. For [010] phonons the elementary relaxation times which relate to the energy are estimated as τE0=5.25×10−13 sec above Tc and τE0=3.32×10−12 sec below Tc. The phonon attenuations are also estimated and compared with the observed ones. For the [001] phonons the elementary relaxation time is estimated as τ0=5.25×10−14 sec, in good agreement with the value obtained from right-angle Brillouin scattering.