LaSr3NiRuO4H4: A 4d Transition‐Metal Oxide–Hydride Containing Metal Hydride Sheets

The synthesis of the first 4d transition metal oxide–hydride, LaSr3NiRuO4H4, is prepared via topochemical anion exchange. Neutron diffraction data show that the hydride ions occupy the equatorial anion sites in the host lattice and as a result the Ru and Ni cations are located in a plane containing only hydride ligands, a unique structural feature with obvious parallels to the CuO2 sheets present in the superconducting cuprates. DFT calculations confirm the presence of S=1/2 Ni+ and S=0, Ru2+ centers, but neutron diffraction and μSR data show no evidence for long‐range magnetic order between the Ni centers down to 1.8 K. The observed weak inter‐cation magnetic coupling can be attributed to poor overlap between Ni 3dz2 and H 1s in the super‐exchange pathways. A 4d transition‐metal oxide–hydride, LaSr3NiRuO4H4, is prepared via topochemical anion exchange. Hydride ions occupy equatorial anion sites in the lattice and as a result the Ru and Ni cations are located in a plane containing only hydride ligands.