Material name Cryolite
Composition Na3AlF6
Chemical formula weight 209.94
System Monoclinic
Temperature (ºC) 22
a (Å), b (Å), c (Å) 5.4139(7) 5.6012(5) 7.7769(8) @
α (deg), β (deg), γ (deg) 90 90.183(3) 90 @
Unit cell volume (Å3) 235.83
Calculated density (g/p3) 2.96
Z 2
Space group P21/n (No.14)
atom site g x/a y/b z/c B2)
Na1 2b 1 0 0 1/2 2.7
Na2 4e 1 -0.0121(3) 0.4492(2) 0.2526(2) 4.2
Al 2a 1 0 0 0 1.7
F1 4e 1 0.1016(4) 0.0442(4) 0.2188(2) 3.1
F2 4e 1 0.2278(4) 0.3267(4) 0.5450(3) 3.8
F3 4e 1 0.1622(4) 0.2687(4) 0.9383(3) 4.0
Comment B values were calculated on the basis of βij values in the reference.

Reference: H. Yang, S. Ghose, and D.M. Hatch, Physics and Chemistry of Minerals, 19, 528 (1993).