Halos contain information about the interfacial angles within a crystal, the refractive index and hence the chemical composition of the solid, the crystal symmetry
, the shape of the crystals, and the orientation that falling crystals assume in the air.
In this case, a warning--that there is a lattice/formula match (12) for the two structures and that the metric symmetry exceeds crystal symmetry
for the second structure--would have been helpful.
Transformations for monoclinic crystal symmetry
in texture analysis.
, habit, cleavage, hardness, density, color, luster and transparency).
Research has shown that there exists a close link between metric and crystal symmetry.
As the metric symmetry is highly correlated with the crystal symmetry, such lookup procedures are widely used in modern crystallography--e.
Research with the crystallographic databases has proved that the metric and crystal symmetry are almost always the same.
Because of the link between metric and crystal symmetry, the relationships in Table 2 are routinely used by the Crystallographic Data Centers in the critical evaluation of data.
For example, the selected compounds that were reported in monoclinic space groups but with metric orthorhombic F-centered lattices (reduced form 16, and 26) were shown using MISSYM (25,26) to have the higher crystal symmetry.
and lattice parameters of two other new phases, [BaNd.
In 1784, Hauy's classic Essai d'une Theorie sur la Structure des Crystaux superseded Rome de l'Isle's Cristallographie, firmly establishing the mathematical principles underlying crystal symmetry