Premium
Further studies on the dielectric behaviour of cadmium iodide polytypes
Author(s) -
Fernandez A. M.,
Srivastava O. N.
Publication year - 1977
Publication title -
journal of applied crystallography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.429
H-Index - 162
ISSN - 1600-5767
DOI - 10.1107/s002188987701276x
Subject(s) - dielectric , iodide , materials science , cadmium , crystallography , chemistry , condensed matter physics , inorganic chemistry , physics , metallurgy , optoelectronics
The dielectric constants (ɛ r ) of several cadmium iodide polytypes have been measured and found to be higher than that of the parent 4 H structure. The dielectric constants for several long‐period polytypes have been found to lie between 60 and 190 whereas the 4 H parent structure has a value in the range of about 15 to 30. In particular, both increasing polytype periodicity and increasing disorder increase the dielectric constant, e.g. from 16 for an ordered 4 H structure to 114 for a 32 H structure and 67 for a highly disordered 4 H structure. In the absence of disorder a particular polytype has its own characteristic dielectric constant value, e.g. the two 14 H polytypes which have a common ɛ r value of 63.