Pressure-induced isostructural phase transition of a metal-organic framework Co-2(4,4 '- bpy)(3)(NO3)(4)center dot xH(2)O

Based on the 4,4 '- bipyridine organic linker, metal-organic frameworks of Co-2(4,4 '-bpy)(3)(NO3)(4)center dot xH(2)O (CB-MOF) have been prepared. The pressure-dependent structure evolution of CB-MOF has been investigated up to 11 GPa. An isostructural phase transition was observed at about 6 GPa followed by negative compressibility along the b axis.