New alkaline halogenopalladates(II) with incorporated iodine dumb-bells crystal structures, phase-transitions, and vibrational spectra [German]

摘要

Dark-reddish crystals of Cs-2[PdBr4]I-2, Cs-2[PdCl4]I-2, and black crystals of Rb-2[PdBr4]I-2 were obtained by solvothermal reaction from diluted hydrohalogenic acids and crystallize in space group I4/mmm with Z = 2. Unitcell parameters for Cs-2[PdBr4]I-2 are a = 848.96(1) pm, c = 908.53(2) pm; Cs-2[PdCl4]I-2 a = 814.65(2) pm, c = 899.10(1) pm and for Rb-2[PdBr4]I-2 a = 840.9(1) pm, c = 902.3(1) pm. The compounds contain isolated [PdX4] building units (X = Cl, Br) which are supplemented by embedded iodine dumb-bells. Cs-2[PdBr4]I-2 and Cs-2[PdCl4]I-2 show reversible pressure induced phase transitions above 78 kbar and 199 kbar, respectively. [References: 22]