PACS 72.60.+g, 81.40Vw The resistance of ammonium chloride (NH 4 Cl), fluoride (NH 4 F) and bromide (NH 4 Br) is investigated at pressures from 20 to 50 GPa in the temperature range 77 -400 K. The transition from high-resistance to low-resistance state was found at pressures of about 15 GPa for NH 4 Br, 27 GPa for NH 4 Cl, and 42 GPa for NH 4 F, respectively. The characteristic temperature and pressure of the transition are shown to depend on the duration of the pressure treatment. All the ammonium halides show metal-like behaviour under high pressures similar to that of alkali halides. The non-monotonic temperature dependence of the resistivity, which disappears after sufficiently long pressure treatment, indicates the existence of intermediate states.
The article is devoted to the investigation of electric properties of ferroelectric-semiconducting AgPbAsSe 3 at pressures up to 45 GPa and the existence of phase transitions in this compound. Our data show that there are two phase transitions at 1.5-2 and 31-32 GPa.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.