Properties of water by the IUPAC as being unsuitable for this purpose, since it is already the name of a cyclic ether also known as tetrahydropyran. The simplest systematic name of water is "hydrogen oxide". This is analogous to related compounds such as hydrogen peroxide, hydrogen sulfide, and deuterium oxide (heavy water). Using chemical nomenclature for type I ionic binary compounds, water would take the name "hydrogen monoxide" , but this is not among the names published by the International Union of Pure and Applied Chemistry (IUPAC). Another name is "dihydrogen monoxide", which is a rarely used name of water, and mostly used
Dihydrogen cation of the ion is 1.8 eV. High speed electrons also cause ionization of hydrogen molecules with a peak cross section around 50 eV. The peak cross section for ionization for high speed protons is with a cross section of . A cosmic ray proton at lower energy can also strip an electron off a neutral hydrogen molecule to form a neutral hydrogen atom and the dihydrogen cation, (p + H → H + ) with a peak cross section at around of . An artificial plasma discharge cell can also produce the ion. Dihydrogen cation The hydrogen molecular ion, dihydrogen