Figure 1
Polyhedral representation of hexagonal, triclinic and monoclinic AlPO4 tridymites (from top to bottom). The AlO4 tetrahedra are white and the PO4 tetrahedra are shaded gray. The structure of hexagonal high tridymite is projected along the c axis, and those of triclinic and monoclinic low tridymite in a corresponding orientation are projected along their pseudo-hexagonal axes. |