Ab-initio crystal structure of hydroxy adipate of nickel and hydroxy subarate of nickel and cobalt from synchrotron powder diffraction and magnetic properties

Organic–inorganic hybrid compounds Ni(II)5(OH)6(C6H8O4)2(1), Ni(II)5(OH)6(C8H12O4)2(2) and Co(II)5(OH)6(C8H12O4)2(3) have a similar layered structure as determined ab initio from synchrotron powder diffraction analysis. The metal sites are octahedrally coordinated by O atoms. The slabs are built from edge-sharing octahedra in such a way that channels with an average size of 4 Å are formed. Bis-bidentate and bridging dicarboxylate anions lead to a 3D framework. The compounds (1) and (2) order antiferromagnetically below TN=26.5 and 19.3 K, respectively, while (3) is ferrimagnetic with TC=16.2 K. Crystal data for compounds are as follows: (1)a=11.6504(1) Å, b=6.8021(3) Å, c=6.3603(1) Å, α=73.52(1)°, β=99.69(1)°, γ=96.16(1)°, RB=0.070, 668 reflections; (2)a=13.9325(1) Å, b=6.7893(1) Å, c=6.3534(4) Å, α=73.63(1)°, β=95.14(1)°, γ=91.80(1)°, RB=0.052, 804 reflections; (3)a=13.9806(1) Å, b=6.9588(1) Å, c=6.3967(1) Å, α=73.05(1)°, β=94.51(1)°, γ=92.19(1)°, RB=0.048, 410 reflections. The space group is P−1 for the three compounds.

The hybrid metal-organic compounds Ni(II)5(OH)6(C6H8O4)2(1), Ni(II)5(OH)6(C8H12O4)2(2) and Co(II)5(OH)6(C8H12O4)2(3) have been synthesized by the hydrothermal route. The microporous metal hydroxide layers are bridged by dicarboxylates anions. (1) and (2) are antiferromagnetic with TN=26.5 and 19.3 K, respectively, while (3) is ferrimagnetic with TC=16.2 K.Figure optionsDownload as PowerPoint slide