Synthesis and Crystal Structures of the Calcium Silicon Phosphides Ca 2 Si 2 P 4 , Ca 3 Si 8 P 14 and Ca 3 Si 2 P 4

Three calcium silicon phosphides: Ca 2 Si 2 P 4 , Ca 3 Si 8 P 14 , and Ca 3 Si 2 P 4 were synthesized by solid state reaction and identified by single‐crystal X‐ray diffraction. Ca 2 Si 2 P 4 crystallizes in the noncentrosymmetric space group P 4 1 2 1 2 (no.92) with a = 7.173 Å, c = 26.295 Å. Both Ca 3 Si 8 P 14 and Ca 3 Si 2 P 4 crystallize in the space group P 2 1 / c (no.14) with a = 12.138 Å, b = 13.476 Å, c = 6.2176 Å, β = 90.934°, and a = 7.073 Å, b = 17.210 Å, c = 6.918 Å, β = 111.791°, respectively. The Si–P tetrahedra construct one‐dimensional (1D), two‐dimensional (2D), and three‐dimensional (3D) networks in Ca 3 Si 2 P 4 , Ca 2 Si 2 P 4 , and Ca 3 Si 8 P 14 , respectively, and their calculated bandgaps are 0.826, 0.984, and 0.829 eV, respectively.