The present volume, Fluorine Suppt. Vol. 4, covers the oxygen compounds of fluorine and the binary fluorine-nitrogen compounds. In the first part Fluorine and Oxygen , oxygen fluorides OnF m are described in the order of decreasing F: 0 ratio. It finishes with a description of hyperfluorous acid HOF. The second part Fluorine and Nitrogen deals with the binary fluorine-nitrogen com? pounds. They are subdivided on the basis of the number of nitrogen atoms per molecule. Thus, species such as NFt, NF , NF , and NF are considered first followed by the dinitrogen and 3 2 trinitrogen fluorides NF, NF, and NF and related ions. 2 4 2 2 3 The other compounds under the heading Fluorine and Nitrogen , the fluorine-nitrogen? hydrogen and the fluorine-nitrogen-oxygen(-hydrogen) compounds, will be covered in Fluorine Suppt. Vol. 5. Intense development in the field of inorganic fluorine-oxygen and fluorine nitrogen chem? istry began in the middle of the 1950s when in less than a decade numerous previously unknown compounds and a great deal of new information were produced. Research in this field was strongly stimulated by interest in these compounds as potential high-energy oxi? dizers for rocket fuels. That is also the reason why much of the pertinent chemical information is found in patent Iiterature and U.S. Government contractor reports.With contributions by numerous expertsThe present volume, Fluorine Suppt. Vol. 4, covers the oxygen compounds of fluorine and the binary fluorine-nitrogen compounds. In the first part Fluorine and Oxygen , oxygen fluorides OnF m are described in the order of decreasing F: 0 ratio. It finishes with a description of hyperfluorous acid HOF. The second part Fluorine and Nitrogen deals with the binary fluorine-nitrogen com? pounds. They are subdivided on the basis of the number of nitrogen atoms per molecule. Thus, species such as NFt, NF , NF , and NF are considered first followed by the dinitrogen and 3 2 trinitrogen fluorides NF, NF, lS8