Study of Dielectric Properties and Ultrasonic Attenuation in KDP-Type Ferroelectrics

Table 2

Calculated values of and for KDP crystal for different values of four-body coupling coefficient .

Temperature (K)
20	0.500	0.499	0.499	0.454	0.369	0.311
40	0.498	0.499	0.499	0.455	0.369	0.311
60	0.459	0.481	0.498	0.460	0.376	0.312
80	0.257	0.278	0.487	0.482	0.446	0.317
100	0.137	0.143	0.454	0.489	0.479	0.332
120	0.102	0.104	0.409	0.490	0.485	0.354
122	0.100	0.100	0.403	0.491	0.486	0.357
123	0.000	0.000	0.400	0.492	0.492	0.358
125	0.000	0.000	0.398	0.484	0.484	0.449
130	0.000	0.000	0.389	0.468	0.468	0.457
135	0.000	0.000	0.373	0.446	0.446	0.443
140	0.000	0.000	0.352	0.426	0.426	0.436
145	0.000	0.000	0.320	0.408	0.408	0.410
150	0.000	0.000	0.300	0.396	0.396	0.392