The published structure of La2NiO4+y has unusually short (1.94 ) Ni-O bond lengths. We reexamined the structure of La2NiO4.18 using monochromatic synchrotron x-ray radiation. Rietveld refinement of the structure in space group Bbcm yielded Fourier synthesis (Fobs) maps that suggest a modified structural model for La2NiO4.18. The refined structure contains chemically more reasonable interatomic distances (e.g., shortest Ni-O distance of 2.00 ). A comparison of this structure with that of the superconductor La2CuO4+y reveals disparities in the conduction planes of the two materials that may explain differences in electrical behavior.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics