Class PdbxReflnsTwin

  • All Implemented Interfaces:
    Category

    @Generated("org.rcsb.cif.generator.SchemaGenerator")
    public class PdbxReflnsTwin
    extends BaseCategory
    Details decribing crystallographic twinning.
    • Constructor Detail

      • PdbxReflnsTwin

        public PdbxReflnsTwin​(String name,
                              int rowCount,
                              Object[] encodedColumns)
      • PdbxReflnsTwin

        public PdbxReflnsTwin​(String name)
    • Method Detail

      • getDiffrnId

        public StrColumn getDiffrnId()
        The diffraction data set identifier. A reference to _diffrn.id in category DIFFRN.
        Returns:
        StrColumn
      • getCrystalId

        public StrColumn getCrystalId()
        The crystal identifier. A reference to _exptl_crystal.id in category EXPTL_CRYSTAL.
        Returns:
        StrColumn
      • getDomainId

        public StrColumn getDomainId()
        An identifier for the twin domain.
        Returns:
        StrColumn
      • getType

        public StrColumn getType()
        There are two types of twinning: merohedral or hemihedral non-merohedral or epitaxial For merohedral twinning the diffraction patterns from the different domains are completely superimposable. Hemihedral twinning is a special case of merohedral twinning. It only involves two distinct domains. Pseudo-merohedral twinning is a subclass merohedral twinning in which lattice is coincidentally superimposable. In the case of non-merohedral or epitaxial twinning the reciprocal lattices do not superimpose exactly. In this case the diffraction pattern consists of two (or more) interpenetrating lattices, which can in principle be separated.
        Returns:
        StrColumn
      • getOperator

        public StrColumn getOperator()
        The possible merohedral or hemihedral twinning operators for different point groups are: True point group Twin operation hkl related to 3 2 along a,b h,-h-k,-l 2 along a*,b* h+k,-k,-l 2 along c -h,-k,l 4 2 along a,b,a*,b* h,-k,-l 6 2 along a,b,a*,b* h,-h-k,-l 321 2 along a*,b*,c -h,-k,l 312 2 along a,b,c -h,-k,l 23 4 along a,b,c k,-h,l References: Yeates, T.O. (1997) Methods in Enzymology 276, 344-358. Detecting and Overcoming Crystal Twinning. and information from the following on-line sites: CNS site http://cns.csb.yale.edu/v1.1/ CCP4 site http://www.ccp4.ac.uk/dist/html/detwin.html SHELX site http://shelx.uni-ac.gwdg.de/~rherbst/twin.html
        Returns:
        StrColumn
      • getFraction

        public FloatColumn getFraction()
        The twin fraction or twin factor represents a quantitative parameter for the crystal twinning. The value 0 represents no twinning, < 0.5 partial twinning, = 0.5 for perfect twinning.
        Returns:
        FloatColumn
      • getMeanI2OverMeanISquare

        public FloatColumn getMeanI2OverMeanISquare()
        The ideal statistics for twinned crystals. The values calculated with the acentric data are given below. Statistic Untwinned data Perfect twinned data <I^2>/<I>^2 2.0 1.5 <F>^2/<F^2> 0.785 0.865 References: Yeates, T.O. (1997) Methods in Enzymology 276, 344-358. Detecting and Overcoming Crystal Twinning. and information from the following on-line sites: CNS site http://cns.csb.yale.edu/v1.1/ CCP4 site http://www.ccp4.ac.uk/dist/html/detwin.html SHELX site http://shelx.uni-ac.gwdg.de/~rherbst/twin.html
        Returns:
        FloatColumn
      • getMeanFSquareOverMeanF2

        public FloatColumn getMeanFSquareOverMeanF2()
        The ideal statistics for twinned crystals. The values calculated with the acentric data are given below. Statistic Untwinned data Perfect twinned data <I^2>/<I>^2 2.0 1.5 <F>^2/<F^2> 0.785 0.865 References: Yeates, T.O. (1997) Methods in Enzymology 276, 344-358. Detecting and Overcoming Crystal Twinning. and information from the following on-line sites: CNS site http://cns.csb.yale.edu/v1.1/ CCP4 site http://www.ccp4.ac.uk/dist/html/detwin.html SHELX site http://shelx.uni-ac.gwdg.de/~rherbst/twin.html
        Returns:
        FloatColumn