AM1 energies.

Note reduced distance between N-1 and 4-amino N atoms in all the diprotonated forms and increased separation of quinolines N1 in tetraprotonated forms of DCQ.注：所有双质子化形式的DCQ中，N-1与4-氨基氮原子之间的距离均有所缩短；而其四质子化形式中，喹啉N1原子的间距则有所增大。