Pd₁₇In₄Se₄, a Metal‐Rich Palladium–Indium Selenide with an Open‐Framework Structure

Abstract

Abstract A new metal‐rich palladium–indium selenide, Pd 17 In 4 Se 4 , was synthesized in the shape of needlelike crystals by annealing a mixture of the elements in a 7:2:1 ratio, respectively, at 750 °C for 7–10 d with subsequent cooling to room temperature. Its crystal structure was determined from single‐crystal diffraction data, with the composition confirmed by energy‐dispersive spectroscopy (EDS). The compound crystallizes in a new structure type [tetragonal, I 4/ m , a = 14.3104(7) Å, c = 3.9641(4) Å, Z = 2]. Its main structural units are indium‐centered [Pd 12 In] cuboctahedra of the Cu 3 Au type. The key feature that differentiates the structure of Pd 17 In 4 Se 4 from any known compound based on the Pd–In intermetallic motif is the terminal role of selenium atoms that results in the formation of 1D channels along the c axis. Electronic structure calculations on the DFT/full‐potential linearized augmented‐plane wave (FP‐LAPW) level predict metallic properties and Pauli‐like paramagnetic behavior for the new compound. The electron localization function (ELF) topological analysis reveals the key role of selenium lone pairs in the formation of the channels in the structure and shows the multicentered nature of the bonding in the [Pd 12 In] fragments.