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MINERALS AND SYNTHETIC COMPOUNDS, AmXn, IN WHICH X
ATOMS ARE |
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CLOSE PACKED AND A ATOMS OCCUPY OCTAHEDRAL INTERSTICES |
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Rutile |
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click here to see a key to this data bar
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octa |
50% |
hcp |
3-d |
2
edges, 2 vertices |
A-
6c, X- 3c/hcp |
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structure |
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The rutile structure is
comprised of HCP packed X atoms with A atoms occupying |
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50% of the octahedral interstices of each
successive layer. |
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Ex. TiO2 ( titanium dioxide,
rutile ) ( Ti - A , O - X ) |
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Crystal lattice |
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The HCP lattice model
for rutile shows that the occupied AX6 groups in each layer |
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are linked into continuous chains that are
separated by rows of unoccupied voids. |
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Chains in successive layers are staggered
relative to each other so that they are |
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linked by their vertices. |
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Figure 86 -
Rutile lattice structure |
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click image to enlarge |
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Polyhedral framework |
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linking surfaces |
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Figure 87 -
Rutile polyhedral |
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framework model |
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( 86T, 116 pinges ) |
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2
edges, 2 vertices |
click image to enlarge |
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The occupied AX6
chains are clearly revealed in the polyhedral framework model |
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as well as their linkage. |
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Cleavage |
Crystal habit |
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(111) - perfect, (100) - good, (110) - good |
prismatic |
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Isostructural minerals/compounds |
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MgF2, FeF2, CoF2,
NiF2, MnF2, ZnF2, GeO2 (low),
SnO2, PbO2, a-MnO2,
RuO2, IrO2, |
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FeTa2O6, MgSb2O,
SiO2 (stishovite) |
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Page
57 - Structure matters - Rutile |
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