Cu12-cluster-based metal–organic framework as a metastable intermediate in the formation of a layered copper phosphonate

Abstract

The solvothermal reaction of CuSO₄·5H₂O and a chiral R-pempH₂ ligand (molar ratio 6 : 1) first forms the metastable intermediate [Cu₂₄(OH)₂₀(R-pempH)₈(SO₄)₁₀(H₂O)_10.5]·35H₂O (1), followed by the formation of the stable phase [Cu₂(OH)(R-pempH)(SO₄)(H₂O)]·H₂O (2). Compound 1 displays a novel 3D open-framework structure containing Cu₁₂ cluster nodes and sulfate links, which can be converted to the layered compound 2. We also investigated the photothermal effects of both compounds.