HIGH-PRESSURE SYNTHESIS AND STRUCTURE OF NA2PDH4

The ternary sodium palladium hydride Na2PdH4 and its analogous deuteri de were prepared via the reaction of sodium hydride (deuteride) with p alladium sponge at 770 K and 1800 bar hydrogen (deuterium) pressure. I ts structure was determined from X-ray diffraction studies of powder s amples in the temperature range 9 to 600 K and an elastic neutron diff raction experiment on the deuterium compound at room temperature. The atomic arrangement in Na2PdH4 contains isolated square-planar [PdH4](2 -) groups and is isotypic with that of Na2PtH4 (space group 14/minin, Z = 2).