Institute of Experimental Mineralogy Russian Academy of Sciences ------------------------------------------------- 142432, Chernogolovka, Moscow district A.V. Chichagov +7(496)52-22320 *** *** W W W - X R A Y P O L *** *********************** MAGNESIOCHROMITE 3, t-spinel, syn, f-oxospinelides, sf-spinel, s-chromite Mg(0.80)Fe(0.20)Cr(2)O(4) Cubic * Fd3m Z = 8 *Fd3m 21 .8 .9 Ref.Str.: Lenaz D., Skogby H., Princivalle F., Halenius U. (2004) * Phys. Chem. Minerals, 31, 633-642 R: N.A.D. Initial data from BDM-file Lattice parameters (cub. angs.,degr.): a = 8.3415 alpha = 90.0 b = 8.3415 beta = 90.0 c = 8.3415 gamma = 90.0 Unit cell volume (cub. angs.) = 580.41 Molar volume ( cub.cm/mol.) = 43.7 Co-ordinates, thermal parameters, occupation for atomic positions: NoP x/a y/b z/c B(j) atom / occupation 1 0.125 0.125 0.125 0.0 Mg = 0.63, Fe = 0.37 2 0.5 0.5 0.5 0.0 Cr = 1.00 3 0.2615 0.2615 0.2615 0.0 O = 1.00 Co-ordinates for all atomic positions : No NoP x/a y/b z/c 1 1 0.125 0.125 0.125 2 2 0.5 0.5 0.5 3 3 0.2615 0.2615 0.2615 4 1 0.875 0.875 0.875 5 3 0.7385 0.7385 0.7385 6 1 0.375 0.875 0.375 7 1 0.625 0.125 0.625 8 1 0.375 0.375 0.875 9 2 0.0 0.25 0.75 10 2 0.25 0.75 0.0 11 2 0.75 0.0 0.25 12 3 0.2385 0.0115 0.5115 13 3 0.4885 0.9885 0.7615 14 3 0.5115 0.2385 0.0115 15 1 0.625 0.625 0.125 16 1 0.875 0.375 0.375 17 1 0.125 0.625 0.625 18 3 0.7615 0.4885 0.9885 19 3 0.0115 0.5115 0.2385 20 3 0.9885 0.7615 0.4885 21 2 0.0 0.75 0.25 22 2 0.75 0.25 0.0 23 2 0.25 0.0 0.75 24 3 0.2385 0.5115 0.0115 25 3 0.9885 0.4885 0.7615 26 3 0.0115 0.2385 0.5115 27 3 0.7615 0.9885 0.4885 28 3 0.5115 0.0115 0.2385 29 3 0.4885 0.7615 0.9885 30 2 0.25 0.25 0.5 31 2 0.25 0.5 0.25 32 2 0.0 0.5 0.0 33 2 0.75 0.5 0.75 34 2 0.0 0.0 0.5 35 2 0.5 0.25 0.25 36 2 0.5 0.0 0.0 37 2 0.5 0.75 0.75 38 2 0.75 0.75 0.5 39 3 0.4885 0.4885 0.2615 40 3 0.0115 0.7385 0.0115 41 3 0.7615 0.2615 0.7615 42 3 0.5115 0.7385 0.5115 43 3 0.7615 0.7615 0.2615 44 3 0.7385 0.0115 0.0115 45 3 0.2615 0.7615 0.7615 46 3 0.7385 0.5115 0.5115 47 3 0.9885 0.9885 0.2615 48 3 0.0115 0.0115 0.7385 49 3 0.4885 0.2615 0.4885 50 3 0.2385 0.7385 0.2385 51 3 0.9885 0.2615 0.9885 52 3 0.2385 0.2385 0.7385 53 3 0.2615 0.4885 0.4885 54 3 0.7385 0.2385 0.2385 55 3 0.2615 0.9885 0.9885 56 3 0.5115 0.5115 0.7385 X-ray density (g/cm cub.) = 4.67 MU (1/cm) = 978.42 Mass attenuation coefficient (cm**2/g) = 209.656 Selected interatomic distances (cation-anion,anion-anion): NoP Atom Rad.sph. C.N. Distance NoP N. (angs.) (angs.) 1 Mg ,Fe 2.592 4 1.9721 3 1.9721 3 1.9721 3 1.9721 3 2 Cr 2.628 6 1.9941 3 1.9941 3 1.9941 3 1.9941 3 1.9941 3 1.9941 3 3 O 3.264 12 2.9554 3 2.9554 3 2.9554 3 2.9554 3 2.9554 3 2.9554 3 2.6778 3 3.2205 3 2.6778 3 3.2205 3 2.6778 3 3.2205 3 X-ray diffraction powder data (II), X-Ray W.L. = 1.78892(angs.): No H K L Theta 2*Theta S LPG MF F I int. ( degree ) *100 1 1 1 1 10.704 21.407 0.104 55.08 8 111.8 1633.4 2 2 2 0 17.655 35.311 0.17 19.01 12 112.8 861.0 3 3 1 0 19.822 39.643 0.19 14.73 24 0.0 0.0 4 1 1 3 20.833 41.666 0.199 13.18 24 212.9 4257.7 5 2 2 2 21.805 43.611 0.208 11.9 8 117.7 391.1 6 4 0 0 25.399 50.798 0.24 8.42 6 326.1 1595.3 7 3 3 1 27.866 55.732 0.261 6.82 24 37.8 69.6 8 2 2 4 31.69 63.379 0.294 5.11 24 85.5 266.3 9 1 1 5 33.861 67.723 0.311 4.44 24 208.1 1368.1 10 3 3 3 33.861 67.723 0.311 4.44 8 137.8 200.2 11 4 4 0 37.343 74.686 0.339 3.66 12 408.2 2170.7 12 5 3 0 38.701 77.402 0.35 3.43 24 0.0 0.0 13 5 3 1 39.374 78.748 0.355 3.34 48 62.6 186.3 14 4 4 2 40.044 80.089 0.36 3.25 24 8.7 1.8 15 6 2 0 42.702 85.404 0.379 2.98 24 69.0 100.9 16 3 3 5 44.681 89.361 0.393 2.84 24 148.9 449.5 X-ray diffraction powder data (I)...X-Ray wave length = 1.78892 (angs.): No H K L Theta 2*Theta d I int I int.n. I p.h.n. H(Si) ( degree ) (angstrem) *100 *100 1 1 1 1 10.704 21.407 4.81597 1633.4 38.4 39.0 5.6 2 2 2 0 17.655 35.311 2.94917 861.0 20.2 20.3 5.7 3 1 1 3 20.833 41.666 2.51506 4257.7 100.0 100.0 5.7 4 2 2 2 21.805 43.611 2.40798 391.1 9.2 9.2 5.7 5 4 0 0 25.399 50.798 2.08538 1595.3 37.5 37.1 5.8 6 3 3 1 27.866 55.732 1.91367 69.6 1.6 1.6 5.8 7 2 2 4 31.69 63.379 1.7027 266.3 6.3 6.1 5.9 8 1 1 5 33.861 67.723 1.60532 1568.3 36.8 35.6 5.9 9 4 4 0 37.343 74.686 1.47458 2170.7 51.0 48.6 6.0 10 5 3 1 39.374 78.748 1.40997 186.3 4.4 4.1 6.0 11 6 2 0 42.702 85.404 1.31891 100.9 2.4 2.2 6.1 12 3 3 5 44.681 89.361 1.27207 449.5 10.6 9.7 6.2 Reference: Chichagov A.V. et al. Information-Calculating System on Crystal Structure Data of Minerals (MINCRYST) - Kristallographiya, v.35, n.3, 1990, p.610-616 (in Russian) |