Ultrasonic study of elastic anisotropy of unidirectional Rochelle salt single crystals grown using the Sankaranarayanan-Ramasamy method

Sodium potassium tartrate tetrahydrate-NaKC4H4O6·4H2O known as Rochelle salt is a well-known ferroelectric. This paper deals with the following topics: (i) the Sankaranarayanan-Ramasamy method of growth of a parallelepiped-shaped single crystal of Rochelle salt having the (1 0 0), (0 1 0) and (0 0 1) planes mutually perpendicular to each other, (ii) evaluation of the second-order elastic stiffness constants C11, C22, C33, C44, C55 and C66 using the parallelepiped-shaped single-crystal sample of Rochelle salt, (iii) growth of large [0 1 1]-, [1 0 1]- and [1 1 0]-oriented cylindrical-shaped single crystals of Rochelle salt from appropriately prepared seeds using the same method, (iv) determination of elastic constants C23, C13 and C12 using the [0 1 1]-, [1 0 1]- and [1 1 0]-oriented single-crystal samples of Rochelle salt, respectively, and (v) calculations of elastic compliance constants S11, S22, S33, S44, S55, S66, S12, S23and S13, Young's modulus E, bulk modulus K, Poisson's ratio υ, linear compressibility β1, β2 and β3 along the three principal directions and volume compressibility β of the crystal.