type: Hooke
references:
  - G.N. Kamm and G.A. Alers,
    Journal of Applied Physics 35:327-330, 1964,
    https://doi.org/10.1063/1.1713309
  - D. Gerlich and E.S. Fisher,
    Journal of Physics and Chemistry of Solids 30:1197-1205, 1969
    https://doi.org/10.1016/0022-3697(69)90377-1

T_ref: 300

C_11: 106.1e+9
C_11,T: -359.3e+5
C_11,T^2: -152.7e+2

C_12: 57.83e+9
C_12,T: -781.6e+4
C_12,T^2: -551.3e+1

C_44: 24.31e+9
C_44,T: -142.9e+5
C_44,T^2: -404.6e+1