• P Hemagiri Rao

Articles written in Pramana – Journal of Physics

• Piezoelectricity in quasicrystals: A group-theoretical study

Group-theoretical methods have been accepted as exact and reliable tools in studying the physical properties of crystals and quasicrystalline materials. By group representation theory, the maximum number of non-vanishing and independent second- order piezoelectric coefficients required by the seven pentagonal and two icosahedral point groups - that describe the quasicrystal symmetry groups in two and three dimensions - is determined. The schemes of non-vanishing and independent second-order piezoelectric tensor components needed by the nine point groups with five-fold rotations are identified and tabulated employing a compact notation. The results of this group-theoretical study are briefly discussed.

• Allowable irreducible representations of the point groups with five-fold rotational axes

Allowable irreducible representations of the point groups with five-fold rotations – that represent the symmetry of the quasicrystals in two and three dimensions – are derived by employing the little group technique in conjunction with the solvability property. The point groups $D_{5h}(\bar{10}m2)$ and $I_{h}(\dfrac{2}{m} \bar{3} \bar{5})$ are taken to illustrate the method.

• Pramana – Journal of Physics

Volume 96, 2022
All articles
Continuous Article Publishing mode

• Editorial Note on Continuous Article Publication

Posted on July 25, 2019