IUPAC Green Book

Mills, I., Cvitas, T., Homann, K. et al., Quantities, Units and Symbols in Physical Chemistry (IUPAC Green Book), Blackwell Science, Oxford (1998). 

By convention, physical quantities are organized in the International System (SI) of quantities and units, which is built upon seven base quantities (Table 1.1), each of which is regarded as having its own dimension. The current definitions of the corresponding base units are given in the IUPAC Green Book, Quantities, Units and Symbols in Physical Chemistry.10 A clear distinction should be drawn between the names of units and their symbols, e.g. mole and mol, respectively. 

High precision values and additional data are available in CODATA1564 and in the IUPAC Green Book.10 Permittivity of vacuum. 

The first IUPAC Manual of Symbols and Terminology for Physicochemical Quantities and Units (the Green Book) of which this is the direct successor, was published in 1969, with the object of securing clarity and precision, and wider agreement in the use of symbols, by chemists in different countries, among physicists, chemists apd engineers, pnd by editors of scientific journals . Subsequent revisions have taken account of many developments in the field, culminating in the major extension and revision represented by the 1988 edition under the simplified title Quantities, Units and Symbols in Physical Chemistry. 

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