Neue Tetrapnictidotitanate(IV): Na3M3[TiX4] mit M  Na/Sr,Na/Eu und X  P,As

New Tetrapnictidotitanates(IV): Na₃M₃TiX₄] with M ? Na/Sr, Na/Eu and X ? P, As The four novel tetrapnictidotitanates(IV) Na₄Sr₂TiP₄, Na₄Sr₂TiAs₄, Na_4.3Eu_1.7TiP₄ and Na_4.3Eu_1.7TiAs₄ were prepared from the binary pnictides NaX, M₃X, M′X (X ? P, As and M′ ? Sr, Eu) and elementary titanium in tantalum ampoules. The air and moisture sensitive transition metal compounds form dark red hexagonal crystals. They are semiconductors with E_g = 1.8eV (Sr) and E_g = 1.3eV (Eu), respectively. The compounds are isotypic with Na₆ZnO₄ (space group P6₃mc (no. 186); hP22; Z = 2; Na₄Sr₂TiP₄; a = 936.8(1) pm, c = 740.5(1) pm; Na₄Sr₂TiAs₄: a = 958.2(1) pm, c = 757.1(1) pm; Na_4.3Eu_1.7TiP₄: a = 929.9(2) pm, c = 732.0(2) pm; Na_4.3Eu_1.7TiAs₄: a = 953.9(1) pm, c = 749.5(1) pm). Main structural units are polar oriented TiP₄]^8? and TiAs₄]^8? tetrahedral anions with d (Ti? P) = 240.2(3) pm and d (Ti? As) = 248.6(3) pm.