Institute of Experimental Mineralogy
Russian Academy of Sciences
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142432, Chernogolovka, Moscow district
A.V. Chichagov +7(496)52-22320
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*** W W W - X R A Y P O L ***
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VILLIAUMITE
1, t-halite, g-villiaumite
NaF
Cubic F m3m Z = 4
Fm3m
28 .5 .1992
Ref.Str.:
Wyckoff R.W.G. (1963)
* Crystal Structures, 1, 85-88
Initial data from BDM-file
Lattice parameters (cub. angs.,degr.):
a = 4.62 alpha = 90.0
b = 4.62 beta = 90.0
c = 4.62 gamma = 90.0
Unit cell volume (cub. angs.) = 98.61
Molar volume ( cub.cm/mol.) = 14.85
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 Na = 1.00
2 0.5 0.5 0.5 0.0 F = 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 2 0.5 0.5 0.5
3 1 0.5 0.0 0.5
4 1 0.5 0.5 0.0
5 1 0.0 0.5 0.5
6 2 0.0 0.5 0.0
7 2 0.0 0.0 0.5
8 2 0.5 0.0 0.0
X-ray density (g/cm cub.) = 2.83
MU (1/cm) = 104.476 Mass attenuation coefficient (cm**2/g) = 36.953
Selected interatomic distances (cation-anion,anion-anion):
NoP Atom Rad.sph. C.N. Distance NoP N.
(angs.) (angs.)
1 Na 2.772 6
2.31 2
2.31 2
2.31 2
2.31 2
2.31 2
2.31 2
2 F 3.192 0
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 19.593 39.186 0.187 15.11 8 6.3 49.9
2 2 0 0 22.781 45.562 0.216 10.78 6 58.1 2247.2
3 2 2 0 33.203 66.405 0.306 4.62 12 47.0 1261.9
4 1 1 3 39.95 79.9 0.359 3.26 24 7.2 41.2
5 2 2 2 42.119 84.238 0.375 3.03 8 39.4 386.7
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 19.593 39.186 2.66736 49.9 2.2 2.2 5.7
2 2 0 0 22.781 45.562 2.31 2247.2 100.0 100.0 5.7
3 2 2 0 33.203 66.405 1.63342 1261.9 56.2 54.6 5.9
4 1 1 3 39.95 79.9 1.39298 41.2 1.8 1.7 6.0
5 2 2 2 42.119 84.238 1.33368 386.7 17.2 16.1 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)
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