[
  {
    "molid": "SM42",
    "smiles": "O=S(=O)(Nc1cc(-c2ccccc2)on1)c1ccccc1",
    "microspecies": [
      {
        "id": "0_1",
        "charge": 0,
        "smiles": "O=S(=O)(Nc1cc(-c2ccccc2)on1)c1ccccc1",
        "std_free_energy": -4.26862907409668,
        "relative_population": 1.0
      },
      {
        "id": "-1_1",
        "charge": -1,
        "smiles": "O=S(=O)([N-]c1cc(-c2ccccc2)on1)c1ccccc1",
        "std_free_energy": -8.549771308898926,
        "relative_population": 1.0
      }
    ],
    "macro_pka_values": [
      {
        "pka_value": 6.62,
        "charge_state_pre": 0,
        "charge_state_post": -1,
        "data_source": "SAMPL7"
      }
    ]
  }
]