Package org.rcsb.cif.schema.core

Class ChemicalFormula

java.lang.Object
org.rcsb.cif.schema.DelegatingCategory.DelegatingCifCoreCategory
org.rcsb.cif.schema.core.ChemicalFormula
All Implemented Interfaces:
Category
@Generated("org.rcsb.cif.schema.generator.SchemaGenerator")
public class ChemicalFormula
extends DelegatingCategory.DelegatingCifCoreCategory
The CATEGORY of data items which specify the composition and chemical properties of the compound. The formula data items must agree with those that specify the density, unit-cell and Z values. The following rules apply to the construction of the data items _chemical_formula.analytical, *.structural and *.sum. For the data item *.moiety the formula construction is broken up into residues or moieties, i.e. groups of atoms that form a molecular unit or molecular ion. The rules given below apply within each moiety but different requirements apply to the way that moieties are connected (see _chemical_formula.moiety). 1. Only recognized element symbols may be used. 2. Each element symbol is followed by a 'count' number. A count of '1' may be omitted. 3. A space or parenthesis must separate each cluster of (element symbol + count). 4. Where a group of elements is enclosed in parentheses, the multiplier for the group must follow the closing parentheses. That is, all element and group multipliers are assumed to be printed as subscripted numbers. [An exception to this rule exists for *.moiety formulae where pre- and post-multipliers are permitted for molecular units]. 5. Unless the elements are ordered in a manner that corresponds to their chemical structure, as in _chemical_formula.structural, the order of the elements within any group or moiety depends on whether or not carbon is present. If carbon is present, the order should be: C, then H, then the other elements in alphabetical order of their symbol. If carbon is not present, the elements are listed purely in alphabetic order of their symbol. This is the 'Hill' system used by Chemical Abstracts. This ordering is used in _chemical_formula.moiety and _chemical_formula.sum. _chemical_formula.iupac '[Mo (C O)4 (C18 H33 P)2]' _chemical_formula.moiety 'C40 H66 Mo O4 P2' _chemical_formula.structural '((C O)4 (P (C6 H11)3)2)Mo' _chemical_formula.sum 'C40 H66 Mo O4 P2' _chemical_formula.weight 768.81

  • Constructor Details

  • Method Details

    • getAnalytical

      public StrColumn getAnalytical()
      Formula determined by standard chemical analysis including trace elements. Parentheses are used only for standard uncertainties (su's).
      Returns:
      StrColumn

    • getIupac

      public StrColumn getIupac()
      Formula expressed in conformance with IUPAC rules for inorganic and metal-organic compounds where these conflict with the rules for any other chemical_formula entries. Typically used for formatting a formula in accordance with journal rules. This should appear in the data block in addition to the most appropriate of the other chemical_formula data names. Ref: IUPAC (1990). Nomenclature of Inorganic Chemistry. Oxford: Blackwell Scientific Publications.
      Returns:
      StrColumn

    • getMoiety

      public StrColumn getMoiety()
      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 Singlege '+' 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.
      Returns:
      StrColumn

    • getStructural

      public StrColumn getStructural()
      This formula should correspond to the structure as reported, i.e. trace elements not included in atom type and atom site lists should not be included. See category description for the rules for writing chemical formulae for inorganics, organometallics, metal complexes etc., in which bonded groups are preserved as discrete entities within parentheses, with post-multipliers as required. The order of the elements should give as much information as possible about the chemical structure. Parentheses may be used and nested as required. This formula should correspond to the structure as actually reported, i.e. trace elements not included in atom-type and atom-site lists should not be included (see also _chemical_formula.analytical).
      Returns:
      StrColumn

    • getSum

      public StrColumn getSum()
      Chemical formulae in which all discrete bonded residues and ions are summed over the constituent elements, following the ordering given in rule 5 of the CATEGORY description. Parentheses normally not used.
      Returns:
      StrColumn

    • getWeight

      public FloatColumn getWeight()
      Mass corresponding to the formulae _chemical_formula.structural, *_iupac, *_moiety or *_sum and, together with the Z value and cell parameters yield the density given as _exptl_crystal.density_diffrn.
      Returns:
      FloatColumn

    • getWeightMeas

      public FloatColumn getWeightMeas()
      Formula mass measured by a non-diffraction experiment.
      Returns:
      FloatColumn