Crystal structure and synchrotron X-ray powder reference pattern for the porous pillared cyanonickelate, Ni(3-amino-4,4′-bipyridine)[Ni(CN)4].

The structure of Ni(3-amino-4,4′-bipyridine)[Ni(CN)₄] (or known as Ni-BpyNH₂) in powder form was determined using synchrotron X-ray diffraction and refined using the Rietveld refinement technique (R = 8.8%). The orthorhombic (C mca) cell parameters were determined to be a = 14.7218(3) Å, b = 22.6615(3) Å, c = 12.3833(3) Å, V = 4131.29(9) ų, and Z = 8. Ni-BpyNH₂ forms a 3-D network, with a 2-D Ni(CN)₄ net connecting to each other via the BpyNH₂ ligands. There are two independent Ni sites on the net. The 2-D nets are connected to each other via the bonding of the pyridine "N" atom to Ni2. The Ni2 site is of six-fold coordination to N with relatively long Ni2–N distances (average of 2.118 Å) as compared to the four-fold coordinated Ni1–C distances (average of 1.850 Å). The Ni(CN)₄ net is arranged in a wave-like fashion. The functional group, –NH₂, is disordered and was found to be in the m -position relative to the N atom of the pyridine ring. Instead of having a unique position, N has ¼ site occupancy in each of the four m -positions. The powder reference diffraction pattern for Ni-BpyNH₂ was prepared and submitted to the Powder Diffraction File (PDF) at the International Centre of Diffraction Data (ICDD). [ABSTRACT FROM AUTHOR]