In order to investigate why crystal symmetry lowers with increasing temperature by phase transition of TII–III (=369 K) in Cs3H(SeO4)2, in spite of the fact that crystal symmetry in the high-temperature phase of many ionic conductors becomes higher by the phase transition, we have studied the relation between the change in crystal symmetry and the appearance of proton motion. It was found from ...

The dispersion relation of plasmons in graphene with a periodic lattice of apertures takes a band structure. Light incident on this plasmonic crystal excites only particular plasmonic modes in select bands. The selection rule is not only frequency/wavevector matching but also symmetry matching, where the symmetry of plasmonic modes originates from the point group symmetry of the lattice. We dem...

An intimate historical and conceptual association exists between crystals and chirality. Yet the relationships between crystal symmetry and crystal morphology are not fully understood. In biological environments, molecular recognition between biological macromolecules and crystal surfaces can affect crystal morphological symmetry, or can be modulated by the symmetry expressed at the surfaces. T...