High-pressure synthesis of bilayer nickelate Sr$_{3}$Ni$_{2}$O$_{5}$Cl$_{2}$ with tetragonal crystal structure

TL;DR

This paper reports the synthesis of a new bilayer nickelate, Sr$_{3}$Ni$_{2}$O$_{5}$Cl$_{2}$, under high pressure, revealing a tetragonal structure similar to a known superconductor, with implications for future superconductivity research.

Contribution

First synthesis of Sr$_{3}$Ni$_{2}$O$_{5}$Cl$_{2}$ under high pressure, confirming its tetragonal structure and structural similarity to a superconductor.

Findings

Synthesized Sr$_{3}$Ni$_{2}$O$_{5}$Cl$_{2}$ at 10 GPa and 1400°C.

Determined crystal structure isostructural with La$_{3}$Ni$_{2}$O$_{7}$.

Structural similarity suggests potential for superconductivity.

Abstract

A novel oxychloride, Sr$_{3}$Ni$_{2}$O$_{5}$Cl$_{2}$, was synthesized for the first time under high pressure of 10 GPa at 1400 ${}^\circ$C, motivated by a theoretical prediction of its potential superconductivity under ambient pressure. Small single crystals were used to determine the crystal structure and measure the temperature dependence of electrical resistance. The crystal is isostructural with the recently discovered superconductor, La$_{3}$Ni$_{2}$O$_{7}$, in line with the theoretical expectation.