Low-temperature thermal expansion of rock-salt ZnO

TL;DR

This study measures the thermal expansion of metastable rock-salt ZnO from 10 to 300 K, revealing no phase transition and quantifying its lattice parameter and volume expansion coefficient.

Contribution

It provides the first detailed measurements of lattice parameter and thermal expansion of rock-salt ZnO across a broad temperature range without observing phase transitions.

Findings

Lattice parameter increases from 4.266 Å at 10 K to 4.2752 Å at 298 K.

Volume thermal expansion coefficient rises to 4.77×10^-5 K^-1 at 298 K.

No phase transition observed down to 10 K.

Abstract

Lattice parameter of metastable high-pressure phase of zinc oxide, rock-salt ZnO was measured in the 10-300 K temperature range using synchrotron X-ray powder diffraction. No phase transition was observed down to 10 K. The lattice parameter of rock-salt ZnO was found to increase from 4.266 {\AA} in the 10-80 K range up to 4.2752(3) {\AA} at 298 K, while the volume thermal expansion coefficient increases from slight negative values below 40 K up to 4.77\times10^-5 K^-1 at 298 K.