E. Haussuhl et E. Tillmanns, PHYSICAL-PROPERTIES AND PHASE-TRANSITIONS OF BIS(GUANIDINIUM)ZIRCONIUM BIS(NITRILOTRIACETATE)HYDRATE, [C(NH2)(3)](2)ZR[N(CH2COO)(3)](2)CENTER-DOT-H2O, Zeitschrift fur Kristallographie, 212(11), 1997, pp. 826-831
Large single crystals of optical quality of bis(guanidinium)zirconium
bis(nitrilotriacetate)hydrate have been grown from aqueous solutions.
Complete elastic, thermoelastic and piezoelastic tensors have been det
ermined by ultrasonic methods. In addition, the tensor of thermal expa
nsion, refractive Indices, dielectric and piezoelectric constants have
been studied in the range between 210 K and 330 K. Most physical prop
erties investigated show a strong anisotropy. The piezoelectric consta
nt d(123) exceeds d(111) of alpha-quartz by a factor of 25. Two higher
-order phase transitions appear at about 287 K and 290 K. The intermed
iate phase exhibits strong anomalies of the temperature and pressure d
ependence of the propagation velocities of quasi-longitudinal elastic
waves having a large component of the displacement vector parallel to
[010].