brief history and overview of the Solubility Data project*
IUPAC Commission V.8 (the IUPAC Commission on
Solubility Data) adopted, at its formation in 1979, the goal of preparing
compilations of all experimental determinations of solubility reported
in the world's chemical literature and, where possible, evaluating
these data critically. This enormous task is approached by considering
systems of two or more well-defined components and producing printed
volumes of compilations and critical evaluations of chemically-related
systems. The methodology used in compilations and critical evaluations
has been described in Chemistry International (1),
in the Series itself (e.g., A.S. Kertes in the Foreword to
Vol. 27/28) and recently in ref. (2). The results
of these efforts are published as volumes in the IUPAC Solubility
Data Series (the SDS) ref. (3).
The Commission particularly encourages work on systems of
widespread chemical interest and of practical concern to chemically-related
areas such as the environment, agriculture, human health and global
climate change. However, in practice, the Commission must rely on
the interests of those highly-qualified contributors who wish to participate.
In earlier years an extensive campaign was undertaken to recruit contributors,
based on their expertise identified through their scientific publications.
The task of compiling data proved to be much larger than expected
initially. For example, in the important systems hydrogen in all solvents,
sufficient material was found to produce a double volume 5/6. Since
publication of that volume in 1981, sufficient newer references have
appeared that a third updated volume could be produced. It has also
proved difficult, especially in solid-liquid systems, to cover the
area in a systematic way, again because, in part, of individual expertise
and interests of contributors.
New contributors who have areas of special expertise,
especially in the difficult area of complex salt systems, are always
welcomed by the Commission. The list of published volumes indicates
that more than 50 scientists from more than a dozen countries have
participated thus far in the Solubility Data Series as editors of
and major contributors to volumes; at least an equal number have also
contributed through various compilations and evaluations. Their names
are to be found on the title pages of individual volumes [to
list of published volumes].
Classification of Systems.
Systems are classified in the first instance as belonging
to one of three categories: gases in liquids, liquids in liquids, or solids
in liquids. Within these categories, further classification is based on
1. Gases in liquids. In this case, a strategy for covering
the most important gases has been devised, and has been carried out systematically,
for the most part. Simple monatomic and homonuclear diatomic gases in water
and aqueous solutions are considered first, followed by heteronuclear diatomics
and gases of increasingly complex molecular structure. With some classes,
such as aliphatic amines, overlap with liquid-liquid systems occurs with
propylamine and higher amines. The methods of reporting and evaluating data
differ sufficiently for gases in liquids and for solids in liquids that
division according to the most frequently encountered state of aggregation
has been inevitable. The strategy is evident from the following list. Unless
specified to the contrary (as in vols. 21, 42, 45/46, 50), all volumes contain
data on gases in all solvents which have been reported in the literature.
1.1 noble gases: vols. 1, 2, 4
1.2 homonuclear diatomic and triatomic gases: vols. 5/6, 7, 10, 12 (part)
1.3 hydrides (groups 13-15 of the periodic table, except carbon): vol. 21
1.4 selected hydrocarbons: vols. 9, 24, 27/28, 57
1.5 amines: vol. 21 (part)
1.6 polyatomic gases containing oxygen: vols. 8, 12 (part), 43, 50, 62
1.7 sulfides, selenides: vol. 32
1.8 halides: vol. 42
1.9 gases in molten salts (special volume): vol. 45/46
2. Liquids in liquids. Here, binary and multicomponent
systems are considered in which the components are normally all liquids
at room temperature and atmospheric pressure. However, because groups of
chemically-related systems are treated together, some systems containing
gaseous or solid components are sometimes included as well. The first area
of focus has been the solubility of organic liquids in water. Volumes have
been organized for classes of organic compounds whose aqueous solubility
is particularly relevant for scientific, industrial and environmental reasons,
limited only by the areas of expertise of available contributors. While
work is continuing on aqueous binary systems involving other classes of
organic compounds, a start has been made on non-aqueous binary and ternary
systems. For example, vol. 56 concerns binary systems of alcohols with hydrocarbons,
and a volume concerning alcohol-hydrocarbon-water systems is in preparation.
The binary systems alcohol-water (vol. 15) and alcohol-hydrocarbon provide
systematic background material for evaluating the ternary systems. These
systems were chosen mainly because of their importance in the manufacture
of fuels. So far, 8 volumes on liquids, or 13% of the total, have been published,
2.1 binary systems containing water
2.1.1 hydrocarbons in water: vols. 37, 38
2.1.2 alcohols in water: vol. 15
2.1.3 esters in water: vols. 48, 49
2.1.4 halogenated aliphatics in water: vol. 60
2.1.5 halogenated aromatics in water: vol. 20
2.2 binary non-aqueous systems
2.2.1 alcohols with hydrocarbons: vol. 56
3. Solids in liquids are divided into several groups:
inorganic, organic and metal-organic salts, organic non-electrolytes. All
salts (inorganic and organic) are classified according to the type of anion.
Non-electrolyte organics are classified by structure. There are special
volumes on pharmaceuticals, many of which are salts. Molten salts and alloys
comprise a final group.
In a typical complex inorganic system, binary, ternary and
higher systems may all be encountered. For binary systems, systematic methods
of evaluation have been devised (2). So far, evaluation of ternary systems
has been relatively simple either because of the paucity of data or the
occurrence of only one solid phase. Volumes in preparation will deal with
more complex systems, such as systems containing common salts of the group
1 and 2 metals and ammonium.
3.1 inorganic salts (for specific cations, see list of volumes)
3.1.1 halides: vols. 11, 22, 40 (part), 47, 65
3.1.2 halates: vols. 14, 30, 40, 44
3.1.3 oxyhalides: vol. 40 (part)
3.1.4 perchlorates: vols. 41, 61
3.1.5 oxides, hydroxides: vol. 23, 52
3.1.5 sulfites, selenites, tellurites: vol. 26
3.1.6 nitrates: vol. 13, 55
3.1.7 phosphates: vol. 31
3.1.8 tetraphenylborates: vol. 18
3.1.9 anions containing C, N and S: vol. 3
3.2 antibiotics: vols. 16/17, 34, 35, 36
3.3 molten systems: vols. 25, 33, 51, 64, 65
3.4 organics: vols. 54, 58, 59
3.5 special systems (mercury): vol. 29
In all three main categories, many projects are in progress,
so that the above list will continue to grow in completeness and in coverage
of important systems. For comments or suggestions on subject matter for
future volumes, contact
1. A.S. Kertes, "Solubility Data Project."
Chem. Int. 8, no. 5 (1986) 25-28.
2. R. Cohen-Adad, J.W. Lorimer, S.L. Phillips and M.
Salomon, "A Consistent Approach to Tabulation of Evaluated Solubility
Data: Application to the Binary Systems RbCl-H2O and UO2(NO3)2H2O."
J. Chem. Info. Comp. Sci. 35 (4) (1995) 675-696.
3. Volumes in the IUPAC Solubility Data Series (SDS)
(volume editors, title, date of publication). > See complete
list of volumes published in the SDS.
*This history is an edited version of a paper published
by John W. Lorimer in Chem. Int. 18, no. 2 (1996) 47-50.