Abstract Three thallium(I) diphosphates with compositions Tl4P2O7, Tl2H2P2O7, Tl2H2P2O7(H2O)0.5 and the mixed-valent thallium(I,III) diphosphate Tl2P2O7 (= TlITlIIIP2O7) were obtained from aqueous solutions using an ion-exchange resin (Tl4P2O7), through thermal treatment of TlH2PO4 at 190 °C and subsequent crystallization from aqueous solutions (Tl2H2P2O7, Tl2H2P2O7(H2O)0.5), and from a phosphate flux at 220 °C (Tl2P2O7). The crystal structures of monoclinic Tl4P2O7 (C2/c, Z = 4) and orthorhombic Tl2H2P2O7 (Pbca, Z = 8) are unique, whereas monoclinic Tl2H2P2O7(H2O)0.5 (C2/c, Z = 8) is isotypic with its potassium analogue, and triclinic Tl2P2O7 (P 1 ‾ $‾{1}$ , Z = 4) crystallizes in the TlInAs2O7 structure type. The crystal structure of Tl2P2O7 is related to that of In2P2O7 (= InIInIIIP2O7; P21/c, Z = 4) by a translationengleiche group-subgroup relationship (t2). IR spectra of Tl4P2O7, Tl2H2P2O7 and Tl2P2O7 are reported and discussed.

中文翻译：

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二磷酸铊

摘要 使用离子交换树脂 (),4P2O7, Tl2H2P2O7(H2O)0.5 和混合价的二磷酸铊 (I,III) Tl2P2O7 (= TlITlIIIP2O7) 从水溶液中获得了三种成分为 Tl4P2O7、Tl2H2P2O7、Tl2H2P2O7(H2O)0.5 的二磷酸铊 (I)通过在 190 °C 下对 TlH2PO4 进行热处理，然后从水溶液 (Tl2H2P2O7、Tl2H2P2O7(H2O)0.5) 和 220 °C 下的磷酸盐熔剂 (Tl2P2O7) 中结晶。单斜晶系 Tl4P2O7 (C2/c, Z = 4) 和斜方晶系 Tl2H2P2O7 (Pbca, Z = 8) 的晶体结构是独特的，而单斜晶系 Tl2H2P2O7(H2O)0.5 (C2/c, Z = 8) 与其钾类似物是同型的和三斜 Tl2P2O7 (P 1 ‾ $‾{1}$ , Z = 4) 以 TlInAs2O7 结构类型结晶。Tl2P2O7 的晶体结构与 In2P2O7 (= InIInIIIP2O7; P21/c, Z = 4) 由平移engleiche 组-子组关系 (t2)。报道并讨论了 Tl4P2O7、Tl2H2P2O7 和 Tl2P2O7 的红外光谱。