[
  {
    "molid": "mol6667",
    "smiles": "O=[N+]([O-])c1c[nH]c([N+](=O)[O-])n1",
    "microspecies": [
      {
        "id": "0_1",
        "charge": 0,
        "smiles": "O=[N+]([O-])c1c[nH]c([N+](=O)[O-])n1",
        "std_free_energy": -2.371664524078369,
        "relative_population": 1.0
      },
      {
        "id": "-1_1",
        "charge": -1,
        "smiles": "O=[N+]([O-])c1c[n-]c([N+](=O)[O-])n1",
        "std_free_energy": -9.361995697021484,
        "relative_population": 1.0
      }
    ],
    "macro_pka_values": [
      {
        "pka_value": 2.86,
        "charge_state_pre": 0,
        "charge_state_post": -1,
        "data_source": "Baltruschat ChEMBL"
      }
    ]
  }
]