Fluorine Chemistry: Volume V

Since the publication of Volumes I and II of "Fluorine Chemistry", much new knowledge has accumulated relative to the general chemistry of fluorine-containing compounds. This chapter is an attempt to bring this subject up to date as of the time of the writing of this book in the year 1962. In the previous volumes divisions of the subject were made such as between organic and inorganic, volatile or nonvolatile, and simple and complex compounds, for convenience of organization. These divisions are of course, purely arbitrary; and the enormous number of fluorine-containing compounds with such wide ranges of variations of properties shows how diffuse are the boundaries between these divisions. A distinction between volatile and nonvolatile must depend upon a choice of the measured volatility at some selected temperature. Likewise, the properties of fluorinecontaining compounds show the inadequacy of dividing descriptive chemistry into organic and inorganic, probably more forcibly than the modern chemistry of the compounds of other elements. It seems to be highly inappropriate to classify together the chemistries of many large fields of compounds under a term which is the negative of another field, regardless of the recognized importance of that field. Much of the new information presented in this chapter is improved or more detailed knowledge in areas already broadly treated in Volumes I and II or is filling in the gaps in these areas. For this material there is made no attempt to complete the subject. New types of compounds have been discovered, and for these the subject is treated more completely. As is traditional in organizing chemical information, the subject is divided into groups of the periodic table and proceeds across the table and down it. A compound is listed under its most significant element other than hydrogen, oxygen, or fluorine, if this can be recognized, otherwise, it may be referred to in several places. If two elements seem equally significant, the compound will most likely be found under the element occurring first as the table is traversed. As the lowest molecular weight compound is hydrogen fluoride, the subject begins with it.