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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MAGNESITE
7, t-calcite, g-calcite
MgCO(3)
Hexagonal R 3(-)c Z = 6
R =0.025 NR =300
8 .2 .1993
Ref.Str.:
Gottlicher S., Vegas A. (1988)
* Acta Cryst., B 44, 362-367
Reserv:
T.V.Ushalovskay
Initial data from BDM-file
Lattice parameters (cub. angs.,degr.):
a = 4.636 alpha = 90.0
b = 4.636 beta = 90.0
c = 15.026 gamma = 120.0
Unit cell volume (cub. angs.) = 279.68
Molar volume ( cub.cm/mol.) = 28.08
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 Mg = 1.00
2 0.0 0.0 0.25 0.0 C = 1.00
3 0.2775 0.0 0.25 0.0 O = 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 0.0 0.0 0.25
3 3 0.2775 0.0 0.25
4 3 0.0 0.2775 0.25
5 3 0.7225 0.7225 0.25
6 1 0.6667 0.3333 0.3333
7 1 0.3333 0.6667 0.6667
8 2 0.6667 0.3333 0.5833
9 2 0.3333 0.6667 0.9167
10 3 0.6667 0.6108 0.5833
11 3 0.0558 0.3892 0.9167
12 3 0.3892 0.0558 0.5833
13 3 0.6108 0.6667 0.9167
14 3 0.9442 0.3333 0.5833
15 3 0.3333 0.9441 0.9167
16 1 0.0 0.0 0.5
17 2 0.0 0.0 0.75
18 3 0.2775 0.2775 0.75
19 3 0.0 0.7225 0.75
20 3 0.7225 0.0 0.75
21 1 0.6667 0.3333 0.8333
22 1 0.3333 0.6667 0.1667
23 2 0.6667 0.3333 0.0833
24 2 0.3333 0.6667 0.4167
25 3 0.6667 0.0558 0.0833
26 3 0.0558 0.6667 0.4167
27 3 0.3892 0.3333 0.0833
28 3 0.6108 0.9442 0.4167
29 3 0.9442 0.6108 0.0833
30 3 0.3333 0.3892 0.4167
X-ray density (g/cm cub.) = 3.0
MU (1/cm) = 55.035 Mass attenuation coefficient (cm**2/g) = 18.329
Selected interatomic distances (cation-anion,anion-anion):
NoP Atom Rad.sph. C.N. Distance NoP N.
(angs.) (angs.)
1 Mg 2.52 6
2.1031 3
2.1032 3
2.1031 3
2.1031 3
2.1031 3
2.1031 3
2 C 1.872 3
1.2865 3
1.2864 3
1.2865 3
3 O 3.264 12
2.9266 3
2.2282 3
2.9267 3
2.9266 3
2.9267 3
2.2282 3
3.0211 3
2.8508 3
2.851 3
3.0209 3
3.0211 3
3.021 3
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 0 -2 12.564 25.128 0.141 39.4 6 5.9 10.3
2 1 0 4 16.309 32.617 0.182 22.59 6 101.4 1781.9
3 0 0 6 17.913 35.827 0.2 18.41 2 70.3 232.3
4 1 1 0 19.409 38.817 0.216 15.43 6 30.7 111.6
5 1 1 3 21.479 42.959 0.238 12.31 12 70.0 924.6
6 2 0 2 23.402 46.803 0.258 10.14 6 56.7 250.4
7 2 0 -4 25.789 51.579 0.282 8.13 6 39.9 99.3
8 1 0 -8 26.921 53.842 0.294 7.38 6 78.2 346.4
9 1 1 6 26.924 53.847 0.294 7.37 12 63.4 455.2
10 2 1 1 30.676 61.352 0.331 5.49 12 34.1 98.1
11 2 1 -2 31.188 62.377 0.336 5.3 12 43.1 151.0
12 1 0 10 33.186 66.372 0.355 4.63 6 14.9 7.9
13 2 1 4 33.193 66.385 0.355 4.63 12 41.6 123.1
14 2 0 8 34.168 68.336 0.365 4.35 6 35.6 42.4
15 1 1 9 34.651 69.303 0.369 4.23 12 46.3 139.2
16 2 1 -5 34.656 69.312 0.369 4.23 12 30.4 59.9
17 3 0 0 35.139 70.279 0.374 4.11 6 92.0 267.2
18 0 0 12 37.963 75.927 0.399 3.55 2 105.2 100.5
19 2 1 7 38.435 76.871 0.404 3.47 12 27.5 40.4
20 2 0 -10 39.817 79.633 0.416 3.28 6 41.1 42.5
21 2 1 -8 40.736 81.471 0.424 3.17 12 37.2 67.2
22 3 0 -6 40.738 81.475 0.424 3.17 6 9.1 2.0
23 3 0 6 40.738 81.475 0.424 3.17 6 9.1 2.0
24 2 2 0 41.652 83.304 0.431 3.07 6 28.4 19.0
25 2 2 3 43.013 86.027 0.443 2.95 12 21.5 21.0
26 3 1 -1 43.919 87.838 0.45 2.89 12 8.4 3.1
27 1 1 12 44.361 88.722 0.454 2.86 12 24.7 26.8
28 3 1 2 44.371 88.742 0.454 2.86 12 6.1 1.6
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 0 4 16.309 32.617 2.74305 1781.9 100.0 100.0 5.6
2 0 0 6 17.913 35.827 2.50433 232.3 13.0 13.0 5.7
3 1 1 0 19.409 38.817 2.318 111.6 6.3 6.2 5.7
4 1 1 3 21.479 42.959 2.10364 924.6 51.9 51.4 5.7
5 2 0 2 23.402 46.803 1.93941 250.4 14.1 13.9 5.7
6 2 0 4 25.789 51.579 1.7705 99.3 5.6 5.5 5.8
7 1 1 6 26.924 53.847 1.70114 801.5 45.0 44.0 5.8
8 2 1 1 30.676 61.352 1.50981 98.1 5.5 5.3 5.8
9 2 1 2 31.188 62.377 1.48745 151.0 8.5 8.2 5.8
10 2 1 4 33.193 66.385 1.40702 130.9 7.3 7.1 5.9
11 2 0 8 34.168 68.336 1.37152 42.4 2.4 2.3 5.9
12 1 1 9 34.651 69.303 1.35474 199.1 11.2 10.7 5.9
13 3 0 0 35.139 70.279 1.3383 267.2 15.0 14.3 5.9
14 0 0 12 37.963 75.927 1.25217 100.5 5.6 5.3 6.0
15 2 1 7 38.435 76.871 1.23912 40.4 2.3 2.1 6.0
16 2 0 10 39.817 79.633 1.20294 42.5 2.4 2.2 6.0
17 2 1 8 40.736 81.471 1.18038 71.2 4.0 3.7 6.1
18 2 2 0 41.652 83.304 1.159 19.0 1.1 1.0 6.1
19 2 2 3 43.013 86.027 1.12916 21.0 1.2 1.1 6.1
20 1 1 12 44.361 88.722 1.1017 28.4 1.6 1.5 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)
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