It arises via protonation of nitrous acid: In its infrared spectrum of its salts, νNO is a strong peak in the range 2150-2400 cm−1.

With base, the reaction generates nitrite: NO+ reacts with aryl amines, ArNH2, to give diazonium salts, ArN+2.

NO+, e.g. as NOBF4, is a strong oxidizing agent:[4] In organic chemistry, it selectively cleaves ethers and oximes, and couples diarylamines.

[5] NOBF4 is a convenient oxidant because the byproduct NO is a gas, which can be swept from the reaction using a stream of N2.

[6] One example involves anisole: Nitrosonium, NO+, is sometimes confused with nitronium, NO+2, the active agent in nitrations.