The ac impedance dielectric spectroscopy is modern techniques widely used in solid state chemistry and electrochemistry.
With its help it is possible to study dynamics of phase transitions under external influence, effects on phase boundaries, to divide the electronic and ionic contributions to an electrical conductivity.
In conditions of superhigh compressions the usual methods of researches in situ are not applicable because of small volume of a sample.
The application of these methods enables to receive the new fundamental data as about properties of materials at high pressure, and dynamics of creation of phases, limits of existence of metastable states and so on.
In the report the features of impedance spectroscopy with reference to high pressure physics are considered. The main approaches to interpretation of experimental data on a base of performances about equivalent circuits of the system "diamond anvil cell - sample " are analyzed.
The outcomes of researches of halogenides of alkali metals permitted surveyed to reveal features of transmission of a charge in a "dielectric - semiconductor-metal" transitions.
The observable peculiarities in dielectric losses can be connected to known phase transition in sulfur. Just in the given interval of pressure amorphization in sulfur induced by pressure is observed.
The research described in this publications was made possible in part by Award No.
REC-005 of the U.S. Civilian Research & Development Foundation for the Independent States of the Former Soviet Union (CRDF) and Grant of the RBRF-2001.