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MINERALS AND SYNTHETIC COMPOUNDS, AmXn, IN WHICH X
ATOMS ARE |
CLOSE PACKED AND A ATOMS OCCUPY OCTAHEDRAL INTERSTICES |
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ZrI3 |
click here to see a key to this data bar
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octa |
1/3 |
hcp |
chain |
2
faces |
A-
6c, X- 2c/hcp |
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structure |
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In the ZrI3
structure the X atoms are packed HCP with 1/3 of the octahedral voids |
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in each successive layer occupied with A atoms.
Therefore the individual layers are |
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isostructural to RhF3 layers.
However, the occupied octahedral interstices of each |
successive layer line up vertically forming an
unbroken chain of AX6 groups that are |
face bonded to each other. |
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Ex. ZrI3
( Zr - A ,
I -
X ) |
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Crystal lattice |
The crystal lattice
model shows that each column of occupied octahedral voids is |
separated from other occupied columns by
hexagonal rings of unoccupied voids. |
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Figure 99 - ZrI3 lattice
structure |
click image to enlarge |
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Polyhedral framework |
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linking surfaces |
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Figure 100 -
ZrI3 polyhedral |
framework model |
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2
faces |
click image to enlarge |
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The columns of occupied
AX6 groups are shown to be normal to the
(111) plane. |
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Isostructural minerals/compounds |
TiCl3, TiBr3, TiI3,
ZrCl3, ZrBr3, HfI3,
MoBr3, RuCl3 |
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Page
64 - Structure matters - ZrI3 |
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