[{"from": "human", "value": "Provide a brief overview of this molecule. [O-1][P][=Branch1][C][=O][=O]"}, {"from": "gpt", "value": "The molecule is a divalent inorganic anion obtained by removal of both protons from phosphonic acid It is a phosphorus oxoanion and a divalent inorganic anion. It is a conjugate base of a phosphonate(1-)."}]