[
  {
    "molid": "mol9231",
    "smiles": "O=[N+]([O-])C(CCCO)[N+](=O)[O-]",
    "microspecies": [
      {
        "id": "0_1",
        "charge": 0,
        "smiles": "O=[N+]([O-])C(CCCO)[N+](=O)[O-]",
        "std_free_energy": -6.416958332061768,
        "relative_population": 1.0
      },
      {
        "id": "-1_1",
        "charge": -1,
        "smiles": "O=[N+]([O-])[C-](CCCO)[N+](=O)[O-]",
        "std_free_energy": -7.61400032043457,
        "relative_population": 0.9999998882984168
      }
    ],
    "macro_pka_values": [
      {
        "pka_value": 5.06,
        "charge_state_pre": 0,
        "charge_state_post": -1,
        "data_source": "IUPAC digitized pKa"
      }
    ]
  }
]