ethane.json

{
  "Chemical JSON": 0,
  "name": "ethane",
  "inchi": "1/C2H6/c1-2/h1-2H3",
  "formula": {
    "concise": "C 2 H 6"
  },
  "atoms": {
    "elements": {
      "number": [  1,   6,   1,   1,   6,   1,   1,   1 ]
    },
    "coords": {
      "3d": [  1.185080, -0.003838,  0.987524,
               0.751621, -0.022441, -0.020839,
               1.166929,  0.833015, -0.569312,
               1.115519, -0.932892, -0.514525,
              -0.751587,  0.022496,  0.020891,
              -1.166882, -0.833372,  0.568699,
              -1.115691,  0.932608,  0.515082,
              -1.184988,  0.004424, -0.987522 ]
    }
  },
  "bonds": {
    "connections": {
      "index": [ 0, 1,
                 1, 2,
                 1, 3,
                 1, 4,
                 4, 5,
                 4, 6,
                 4, 7 ]
    },
    "order": [ 1, 1, 1, 1, 1, 1, 1 ]
  },
  "properties": {
    "molecular weight": 30.0690,
    "melting point": -172,
    "boiling point": -88
  }
}

segfault.py

import chemkit

f = chemkit.MoleculeFile()
f.setFormat("cjson")
f.readString(open("ethane.json").read())