type: Hooke

references:
  - L.J. Slutsky and C.W. Garland,
    Physical Review 107(4):972-976, 1957,
    https://doi.org/10.1103/PhysRev.107.972,
    fit to Tab. I (T_min=100K, T_max=300K)

C_11: 59.50e+9
C_11,T: -1.930e+7
C_11,T^2: -1.215e+4

C_33: 61.72e+9
C_33,T: -2.175e+7
C_33,T^2: -5.624e+3

C_44: 16.46e+9
C_44,T: -1.006e+7
C_44,T^2: -7.692e+3

C_12: 25.62e+9
C_12,T: -2.216e+6
C_12,T^2: -4.138e+3

C_13: 21.46e+9
C_13,T: -1.921e+6
C_13,T^2: -4.283e+3

T_ref: 293.15