Oct 172000
 

Acta Cryst. (2000), B56, 747-749.    [ doi:10.1107/S0108768100008466 ]

The reporting of Uequiv and its standard uncertainty has a chequered history. In spite of the recommendation of the IUCr Commission on Journals that authors use the definition of Uequiv of their own choice, possibly without standard uncertainties, there still seems to be … Read the rest

Jul 011994
 

Acta Cryst.  (1994), A50, 411-437.    [ doi:10.1107/S0108767393012784 ]

Each year, many single-crystal structure analyses are reported that show evidence of over- or under-refinement. Often, the refinement strategies have been naive or over-complex and alternative strategies might have been more effective. The many descriptions of crystallographic and numerical techniques suitable for assisting with the control … Read the rest

Jul 171979
 

Acta Cryst. (1979), A35, 698-699.    [ doi:10.1107/S0567739479001613 ]

The truncated Chebyshev polynomial provides a reliable scheme for the automatic determination of empirical weights for least-squares structure refinement when the errors are a function of |Fo|.… Read the rest

Mar 131972
 

J. Appl. Cryst.  (1972), 5, 250.    [ doi:10.1107/S0021889872099996 ]

The principle of this apparatus is not new (Hope, 1971), but it is reported because of interest shown in its simplicity by visitors to this laboratory. Small samples of the solute are heated in a saturated solution in a poor solvent, and convection and diffusion … Read the rest