Table 6. Atomic coordinates (Å x 104) and equivalent isotropic U(eq) and anisotropic displacement parameters (Å2 x 103) for SL988 n.1. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor. The anisotropic displacement factor exponent takes the form: -2 pi^2 0...0 x y z U(eq) U11 U22 U33 U23 U13 U12 O(11) 3631(2) 3382(2) 1211(4) 8(1) 5(1) 10(1) 7(1) 0(1) 1(1) 1(1) O(12) 3613(2) 1780(2) 6481(4) 7(1) 4(1) 8(1) 9(1) 1(1) 1(1) 0(1) O(21) 6146(2) 5101(2) 3084(4) 8(1) 10(1) 6(1) 9(1) -1(1) 3(1) -1(1) O(22) 6062(2) 9976(2) 8046(4) 10(1) 12(1) 8(1) 9(1) 0(1) 2(1) 2(1) O(31) 6062(2) 2657(2) 50(4) 7(1) 5(1) 10(1) 6(1) -2(1) 1(1) 0(1) O(32) 5979(2) 2409(2) 4985(3) 7(1) 7(1) 9(1) 5(1) 2(1) 1(1) -1(1) Si(1) 5395(1) 3474(1) 2273(1) 5(1) 4(1) 5(1) 5(1) 0(1) 1(1) -1(1) Si(2) 5376(1) 1628(1) 7310(1) 5(1) 4(1) 6(1) 4(1) 0(1) 1(1) 0(1) M11 2500 3480(1) 7500 5(1) 4(1) 6(1) 4(1) 0 1(1) 0 M1 2500 1584(1) 2500 6(1) 6(1) 7(1) 5(1) 0 1(1) 0 M2 2500 5515(1) 2500 9(1) 10(1) 8(1) 6(1) 0 -1(1) 0 M21 2500 9509(1) 7500 11(1) 15(1) 7(1) 8(1) 0 -1(1) 0