Synthesis and Crystal Structure of SnPd3D0.138(7) by Neutron Powder Diffraction

Palladium-rich intermetallic compounds have attracted attention for their use in heterogeneous catalysis and their interesting hydrogenation properties. SnPd₃ was synthesized from the elements using selenium as a mineralizing agent. The stoichiometric composition was confirmed by energy-dispersive X-ray spectra (Sn_0.98(5)Pd_3.02(5)). X-ray diffraction showed an ordered AuCu₃ type structure Pm3 m, a = 397.799(1) pm]. SnPd₃ takes up hydrogen at 703 K under 5.0 MPa, resulting in a volume expansion of 0.4 %. The crystal structure was determined from neutron powder diffraction data of the deuteride. SnPd₃D_0.138(7) belongs to the cubic anti-perovskite type Pm3 m, a = 398.338(11) pm]. Deuterium occupies Pd₆] octahedral sites d(Pd–D) = 199.169(6) pm] in a statistical manner.