[
  {
    "molid": "mol9341",
    "smiles": "O=C(O)c1[nH]c(=O)[nH]c(=O)c1[N+](=O)[O-]",
    "microspecies": [
      {
        "id": "-1_1",
        "charge": -1,
        "smiles": "O=C([O-])c1[nH]c(=O)[nH]c(=O)c1[N+](=O)[O-]",
        "std_free_energy": -10.211872100830078,
        "relative_population": 0.9813000617443328
      },
      {
        "id": "-2_1",
        "charge": -2,
        "smiles": "O=C([O-])c1[n-]c(=O)[nH]c(=O)c1[N+](=O)[O-]",
        "std_free_energy": -6.665678977966309,
        "relative_population": 0.8565352380605237
      },
      {
        "id": "-2_3",
        "charge": -2,
        "smiles": "O=C([O-])c1[nH]c(=O)[n-]c(=O)c1[N+](=O)[O-]",
        "std_free_energy": -4.878046989440918,
        "relative_population": 0.1433463127973101
      }
    ],
    "macro_pka_values": [
      {
        "pka_value": 4.94,
        "charge_state_pre": -1,
        "charge_state_post": -2,
        "data_source": "IUPAC digitized pKa"
      }
    ]
  }
]