The stability, ferroelectricity, and electronic structure of R3c-MgSnO3 and R3c-MgSnO3 under compressive strain were investigated by density functional theory. The calculated phonon frequencies and elastic coefficient indicated that MgSnO3 and MgSnO3 under compressive strain could meet dynamic and mechanical stability. The phonon frequencies, elastic coefficient, and mechanical property have been increased in MgSnO3 under compressive strain, which is explained by the bond length, Bader charge, and electronic structure. The bandgap of R3c-MgSnO3 under compressive strain has been increased to 3.8 eV with an indirect bandgap to enhance optical transparency, which agrees with the experiment. The ferroelectric stability and polarization strength could also be promoted by the compressive strain in MgSnO3. The stability, ferroelectric, mechanical, and photoelectric properties of R3c-MgSnO3 could be controlled by compressive strain.
