Page 74 - Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005)
P. 74
IR-4.6 F O R M U L A E
Examples:
36
1. H[ Cl]
32
2. [ P]Cl 3
2
15
3. [ N]H 2 [ H]
17
13
4. [ C]O[ O]
18
32
5. [ P]O[ F 3 ]
2
6. Ge[ H 2 ]F 2
IR-4.5.3.3 Selectively labelled compounds
A s electively labelled compound may be considered as a m ixture of specifically labelled
compounds. It is indicated by prefixing the formula b y t he nuclide symbol(s) preceded by
any necessary locant(s) (but without multiplying subscripts) enclosed in square b rackets.
Examples:
36
1. [ Cl]SOCl 2
2
2. [ H]PH 3
10
3. [ B]B 2 H 5 Cl
The numbers of possible labels for a g iven p osition may be indicated by subscripts separated
by semicolons a dded to the atomic symbol(s) in the isotopic descriptor.
Example:
2
4. [1- H 1;2 ]SiH 3 OSiH 2 OSiH 3
IR-4.6 O P T I O N A L M O D I F I E R S O F F O R M U L A E
IR-4.6.1 Oxidation state
The oxidation state of an element in a f ormula may be indicated by an oxidation number
written a s a right superscript in Roman numerals. Oxidation state zero may be represented
by the numeral 0 b ut is not usually shown. If an element occurs with more t han one
oxidation state in the same f ormula, the element symbol is repeated, each symbol being
assigned a n umeral, a nd the symbols cited in order of these numerals.
Examples:
V
1. [P 2 Mo 18 O 62 ] 6
2. K[Os VIII (N)O 3 ]
V
3. [Mo 2 Mo VI 4 O 18 ] 2
II IV
4. Pb 2 Pb O 4
0
5. [Os (CO) 5 ]
I
6. [Mn (CO) 5 ]
65