CsTi2Cl7‐II: Synthese,Kristallstruktur und magnetische Eigenschaften

CsTi₂Cl₇‐II: Synthesis, Crystal Structure, and Magnetic Properties Single crystals of a second modification of CsTi₂Cl₇ (II) were obtained from the reaction of CsCl with TiCl₂ and C₆Cl₆ (monoclinic, P2₁/m (No. 11), Z = 2, a = 635.4(3), b = 1163.0(2), c = 728.0(2) pm, β = 91.49(4)°). X‐ray pure powder samples are obtained from the binary components in 1 : 2 molar mixtures of CsCl and TiCl₃ (melting at 900 °C and annealing at 550 °C below the melting point). The crystal structure of CsTi₂Cl₇‐II contains layers of densest packings of spheres of the compositions CsCl₃ and Cl₄, respectively, that are stacked alternatively in the [010] direction according to the sequence … ABAC … Ti³⁺ resides in one quarter of the octahedral holes between these layers in a way that confacial bioctahedra are connected via two common edges forming a zigzag chain running parallel to [010]. This structure with Ti³⁺–Ti³⁺ distances of 323 and 347 pm, respectively, is reflected in the antiferromagnetic behavior with interactions about sixteen times stronger within the dimers than between them (J = –490 cm^–1 bzw. J = –30 cm^–1).