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Core CIF Dictionary version 2.3

_chemical_formula_moiety

Name

'_chemical_formula_moiety'

Category: chemical_formula

Data type: char

Examples:

'C7 H4 Cl Hg N O3 S'
'C12 H17 N4 O S 1+, C6 H2 N3 O7 1-'
'C12 H16 N2 O6, 5(H2 O1)'
"(Cd 2+)3, (C6 N6 Cr 3-)2, 2(H2 O)"

Definition

    	
Formula with each discrete bonded residue or ion shown as a separate moiety. See above _chemical_formula_[] for rules for writing chemical formulae. In addition to the general formulae requirements, the following rules apply: 1. Moieties are separated by commas ','. 2. The order of elements within a moiety follows general rule 5 in _chemical_formula_[]. 3. Parentheses are not used within moieties but may surround a moiety. Parentheses may not be nested. 4. Charges should be placed at the end of the moiety. The charge '+' or '-' may be preceded by a numerical multiplier and should be separated from the last (element symbol + count) by a space. Pre- or post-multipliers may be used for individual moieties.

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