Page 11 - Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005)

G E N E R A L A I M S , F U N C T I O N S A N D M E T H O D S I R-1.2

recommendations and, finally, reference is made in Section IR-1.7 to nomenclature in other
areas of chemistry, underlining t hat inorganic c hemistry is part of an integrated whole.

IR-1.2 H I S T O R Y O F C H E M I C A L N O M E N C L A T U R E

The activities of alchemy a nd of the technical arts practised prior to the founding of what
we now know as the science of chemistry p roduced a r ich vocabulary for describing
chemical substances although the names for individual species gave little indication of
composition. However, almost as soon as the true science of chemistry w as established
a ‘ system’ of chemical nomenclature was developed by Guyton d e M orveau in 1782. 1
Guyton’s s tatement o f t he need for a ‘ constant method of denomination, which helps the
intelligence and relieves the memory’ clearly defines the basic aims of chemical
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nomenclature. His system was extended by a j oint contribution with Lavoisier, Berthollet,
and de Fourcroy and was popularized by Lavoisier. 3 Later, Berzelius championed
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Lavoisier’s ideas, adapting t he nomenclature to the Germanic l anguages, expanding the
system and adding many n ew terms. T his s ystem, formulated before the enunciation of the
atomic theory by Dalton, was based upon the concept of elements forming compounds
with oxygen, the oxides i n t urn reacting w ith each other to form salts; the two-word n ames
in some ways r esembled the binary system introduced by Linnaeus (Carl von Linne ´) f or
plant and animal species.
When atomic theory developed to the point where it was possible t o w rite specific
formulae for the various oxides a nd other binary compounds, n ames reflecting composition
more or less accurately t hen became c ommon; n o n ames reflecting the composition of the
oxosalts w ere ever adopted, however. As the number of inorganic compounds rapidly grew,
the essential pattern of nomenclature was little altered until near the end of the 19th century.
As a n eed arose, a n ame was proposed and nomenclature grew by accretion rather than by
systematization.
When Arrhenius focused attention on ions as well as molecules, it became necessary t o
name charged particles in addition to neutral species. I t w as not deemed necessary t o
develop a n ew nomenclature for salts; cations were d esignated by the names of the
appropriate metal and anions by a m odified name of the non-metal portion.
Along with the theory of coordination, Werner proposed a 5 s ystem of nomenclature for
coordination entities which not only reproduced their compositions but also indicated many
of their structures. Werner’s system was completely additive in that the names of the ligands
were cited, followed by the name o f t he central atom (modified b y t he ending ‘ate’ if the
complex w as an anion). Werner also used structural d escriptors a nd locants. The a dditive
nomenclature system was capable of expansion and adaptation to new compounds and even
to other fi elds of chemistry.

IR-1.2.1 International cooperation on inorganic nomenclature
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In 1892 a c onference in Geneva laid the basis for an internationally accepted s ystem of
organic nomenclature but at that time there was nothing comparable for inorganic
nomenclature. Thus, many ad hoc systems had developed for particular rather than general
purposes, and two or more methods often evolved for naming a g iven c ompound belonging

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