A2B_tI6_139_e_a & a,c/a,z2 --params=3.87,1.64599483204,0.38 & I4/mmm D_{4h}^{17} #139 (ae) & tI6 & $C11_{a}$ & C2Ca & C2Ca & M. {von Stackelberg}, Naturwissenschaften 18, 305-306 (1930) 1.00000000000000 -1.93500000000000 1.93500000000000 3.18500000000000 1.93500000000000 -1.93500000000000 3.18500000000000 1.93500000000000 1.93500000000000 -3.18500000000000 C Ca 2 1 Direct 0.38000000000000 0.38000000000000 0.00000000000000 C (4e) -0.38000000000000 -0.38000000000000 0.00000000000000 C (4e) 0.00000000000000 0.00000000000000 0.00000000000000 Ca (2a)