It is also possible to have four organic substituents on the nitrogen. These species are not amines but are quaternary ammonium cations and have a charged nitrogen center. Quaternary ammonium salts exist with many kinds of anions.
it Is alSo possible To havE foUR oRganic SubstitUeNts oN the nitrOGEn. theSe SPecies Are NOT amines but ArE quAternaRy aMmonium CatiOns ANd have a cHArGed nItRogen cEnter. QUateRNArY ammONIuM sAltS EXiSt wiTh MaNY kiNdS OF aNIonS.