# High-pressure phase relations in Zn2SiO4 system: A first-principles study

## TL;DR

This study uses first-principles DFT calculations to investigate phase relations in the Zn2SiO4 system, identifying potential high-pressure phases and phase transitions.

## Contribution

It provides new insights into high-pressure phase structures of Zn2SiO4, proposing candidate structures for phases III and IV and analyzing phase transition mechanisms.

## Key findings

- Phases III and IV are retrograde phases.
- Na2CrO4- and Ag2CrO4-structured phases are likely high-pressure candidates.
- Phase II transitions to spinel during optimization.

## Abstract

In order to clarify phase relation of Zn2SiO4 system, first-principles DFT calculations of 11 phases were conducted. We confirmed that phases III and IV are retrograde phases. Instead, Na2CrO4- and Ag2CrO4-structured phases are most likely candidate structures for high-pressure phases of III and IV, respectively. A transition of phase II to spinel found during optimization was discussed in relation to similar transition known for nitrides.