The arrangement of the halo arcs around the circular halos is not random but represents a mapping of the crystal symmetry
onto the celestial sphere; for example, the six fold symmetry in the arrangement of the arcs associated with the 46[degrees] circular halo in Fig.
When Fridkin and his colleagues at the Institute of Crystallography in Moscow observed an unusually high photovoltage while studying the ferroelectric antimony sulfide iodide a material that did not have any junction separating the carriers he posited that crystal symmetry
could be the origin for its remarkable photovoltaic properties.
As mentioned above, enlarging the PBGs by the reduction of crystal symmetry
by anisotropic anisotropy is not a good choice, since the asymmetry of diamond lattice provides a better way to open the band gaps at high-symmetry points in the Brillouin zone.
2], the most recent update of this line, the SAXS pattern offers a picture of the nanostructure and nanodomain orientation (1 to 100 nm) while the wide-angle scattering (WAXS) pattern, obtained using x-ray diffraction analysis, illustrates the phase state and crystal symmetry
of the sample.
the metric symmetry is F-centered orthorhombic whereas the crystal symmetry
is reported as C-centered monoclinic (Space Group Cc).
It should be noted that due to the low crystal symmetry
of some major components, e.
The benitoite crystal symmetry
(ditrigonal dipyramidal) had been postulated to exist but was not known in nature until the discovery of the species.
The first two chapters present an overview of crystal symmetry
and the line properties of dislocations.
sd] the crystal symmetry
dictates that two sets of alternating faces are symmetry independent (Fig.
In these chapters we read of the relations between the rhombohedral and orthorhombic carbonates and between calcite and its orthorhombic polymorph, aragonite; of calcite crystal symmetry
, and the concepts of axes, planes and centers of symmetry, and basic crystallographic forms; of pseudomorphism, and pseudomorphing of other species by and after calcite; of optical phenomena like double refraction and the polarization of light; and of fluorescence as a function of trace-element chemistry.
The crystal symmetry
can never exceed the metric symmetry, but it can be less.