Figure 4.

a)–c) Structural models of three polytypes PST‐24A, PST‐24B, and PST‐24C viewed along the c‐axis, showing arrangements DDDD…, SDSD…, and SSSS… along the a‐axis, respectively. Their corresponding space groups are P2₁/c, P $\bar{1}$ , and P2/c, respectively. The cas‐zz chains are colored in yellow, and the d5r units in blue. Only the Si−Si connections are shown for clarity. d)–f) The channel systems in the three polytypes, showing differences in the channel dimensionality: 2D in PST‐24A; bi‐level 2D in PST‐24B; 3D in PST‐24C.