type: thermalexpansion

references:
  - V.T. Deshpande and D.B. Sirdeshmukh,
    Acta Crystallographica 15:294-295, 1962,
    https://doi.org/10.1107/S0365110X62000742,
    fit to Tab. 2 (T_min=30ºC, T_max=210ºC)

Alpha_11: 16.4e-6
Alpha_11,T: 1.799e-08
Alpha_11,T^2: 1.734e-10

Alpha_33: 32.6e-6
Alpha_33,T: 1.387e-08
Alpha_33,T^2: 5.794e-10

T_ref: 293.15