Fig. 5.
Band scheme of CrAs at (A) ambient and (B) high pressures. (C) Charge density projected along the a−c plane. The visualized isosurfaces equal to a charge density of 0.05 e/Å3. Atoms in the front layer (bright colors) are inserted into the interstitials of the back layer (atoms in gloomy colors) upon compression. Charge density projected along the b−c plane. A slice of charge density at the plane of c = 0 Å is shown in contours. The interatomic forces are derived from the gradient of energy, also known as the charge density. Because the charge density is less steep along the b axis, it undoubtedly achieves better compressibility. (D) Charge density projected along the a−c, b−c, and a−b planes of CrAs under 0.4 GPa.