12
This conformation of cis-2-butene has C2v symmetry
 6   2.510251777   0.264150651   1.174347582
 6   1.184367149   0.264150651   0.408847086
 6   1.184367529   0.264150651  -0.923122937
 1   0.235202990   0.264150651   0.956846495
 6   2.510252604   0.264150651  -1.688622658
 1   0.235203734   0.264150651  -1.471122883
 1   3.343299672   0.264150651   0.462134712
 1   2.568309495  -0.630729525   1.804454445
 1   2.568309495   1.159030827   1.804454445
 1   3.343300065   0.264150651  -0.976409276
 1   2.568310676   1.159030827  -2.318729533
 1   2.568310676  -0.630729525  -2.318729533
