Theoretical modifications of CrSi2N4 at extreme conditions

Abstract

Owing to its many desirable properties and potentially very wide application in industry, the Cr-Si-N system is very appealing for research. To this day, several studies have been done regarding thin films or coatings, however, there is a lack of studies done on the CrSiN in bulk. In our previous searches, we have investigated this Cr-Si-N system in two different compositions, Cr2SiN4 and CrSi2N4, and several modifications have been found. Exploring the energy landscape of CrSi2N4, ten modifications have been predicted and presented in our previous study. Aiming to further investigate this system, and explore phases possible to be observed in extreme conditions, a multimethodological approach has been employed. By combining the global searches of the energy landscape with data mining, and the Primitive Cell for Atom Exchange method, we predicted several structure candidates that might exist in extreme conditions. Local optimization of the structure candidates was performed on the DFT level using both, the GGA-PBE and the LDA-PZ approximation due to a comparison of the results.