Supplementary material for: Strain-Induced Changes of Electronic and Optical Properties of Zr-based MXenes

Computational details, more details on the geometrical structure and stability, the convergence of electronic and optical properties, and proper- ties under strain.计算细节、关于几何结构及其稳定性的更详细信息、电子和光学特性的收敛性，以及应变下的性质。