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 *** *********************** NIOBIUM 1, at 18'C Nb Cubic I m3m Z = 2 Im3m 27 .5 .1993 Ref.Str.: Wyckoff R.W.G. (1963) * Crystal Structures, 1, 15-16 R: ATOMIC. N.A.D. Initial data from BDM-file Lattice parameters (cub. angs.,degr.): a = 3.3004 alpha = 90.0 b = 3.3004 beta = 90.0 c = 3.3004 gamma = 90.0 Unit cell volume (cub. angs.) = 35.95 Molar volume ( cub.cm/mol.) = 10.83 Co-ordinates, thermal parameters, occupation for atomic positions: NoP x/a y/b z/c B(j) atom / occupation 1 0.0 0.0 0.0 0.0 Nb = 1.00 Co-ordinates for all atomic positions : No NoP x/a y/b z/c 1 1 0.0 0.0 0.0 2 1 0.5 0.5 0.5 X-ray density (g/cm cub.) = 8.58 MU (1/cm) = 1312.724 Mass attenuation coefficient (cm**2/g) = 153.0 Selected interatomic distances (cation-anion,anion-anion): NoP Atom Rad.sph. C.N. Distance NoP N. (angs.) (angs.) 1 Nb 3.48 14 3.3004 1 3.3004 1 3.3004 1 3.3004 1 3.3004 1 3.3004 1 2.8582 1 2.8582 1 2.8582 1 2.8582 1 2.8582 1 2.8582 1 2.8582 1 2.8582 1 X-ray diffraction powder data (II), X-Ray W.L. = 1.54056(angs.): No H K L Theta 2*Theta S LPG MF F I int. ( degree ) *100 1 1 1 0 19.273 38.545 0.214 15.67 12 62.7 57297.7 2 2 0 0 27.825 55.651 0.303 6.84 6 54.8 9537.4 3 1 1 2 34.868 69.736 0.371 4.18 24 49.6 19110.5 4 2 2 0 41.31 82.619 0.428 3.11 12 46.0 6101.4 X-ray diffraction powder data (I)...X-Ray wave length = 1.54056 (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 0 19.273 38.545 2.33374 57297.7 100.0 100.0 5.7 2 2 0 0 27.825 55.651 1.6502 9537.4 16.6 16.3 5.8 3 1 1 2 34.868 69.736 1.34738 19110.5 33.4 32.0 5.9 4 2 2 0 41.31 82.619 1.16687 6101.4 10.6 9.9 6.1 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) |