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Function to load structure factors corresponding to one of the many 1D structures available within the crone package. The structure factors amplitudes have been generated from calculated data with some simulated error, so that they mimic observed data. Phases are calculated from the correct structure.

Usage

load_data(sname = NULL)

Arguments

sname

A character string. Name of the structure whose data are to be loaded in the workspace. It can be one of:

  • beryllium_fluoride

  • carbon_dioxide

  • cyanate

  • nitronium

  • thiocyanate

  • xenon_difluoride

  • pinkerton2015

Default is NULL, in which case the function returns a list of all structures available.

Value

A named fdata-type list with the following elements:

  • a Real numeric. Unit cell length in angstroms. Always included.

  • SG. Spacegroup 2-letters character string. There are only two symmetries possible when working within 1D crystallography, P1 (no symmetry) and P-1 (inversion through the origin). SG can be either "P1" or "P-1". Always included.

  • hidx. Real numeric array. 1D unique (positive in the 1D context) Miller indices. Always included.

  • Fobs. Real numeric array. Amplitudes of observed structure factors. Not always included.

  • sigFobs. Real numeric array. Errors associated with Fobs. Not always included.

  • Phicalc. Real numeric array. Phases (in degrees) of structure factors calculated from the correct 1D structure. They are normally used to check correctness of Phiobs. Not always included.

Examples

# Load thiocyanate data
fdata <- load_data("thiocyanate")
print(fdata)
#> $a
#> [1] 4.969
#> 
#> $SG
#> [1] "P1"
#> 
#> $hidx
#>  [1]  1  2  3  4  5  6  7  8  9 10
#> 
#> $Fobs
#>  [1]  6.613 12.467  9.226  3.454  2.308  0.752  0.304  0.088  0.054  0.002
#> 
#> $sigFobs
#>  [1] 1.208 1.703 1.293 0.862 0.435 0.380 0.424 0.373 0.328 0.414
#> 
#> $Phicalc
#>  [1]   75.7  147.7 -149.9  -57.2   -1.6   74.3  149.1 -141.8  -67.5    4.4
#> 

# Default returns all names of structures included
load_data()
#> 
#> 1D data available for loading:
#> 
#>    beryllium_fluoride
#>    carbon_dioxide
#>    cyanate
#>    nitronium
#>    thiocyanate
#>    xenon_difluoride
#>    pinkerton2015
#> Please use an appropriate name - e.g. load_data("cyanate")