SIR92 recognizes the following commands:
%INITIALIZE initialize the direct access file (to override previous results and data) %DATA Data input routine %NORMAL normalization routine %SEMINV seminvariants routine %INVARIANTS invariants routine %PHASE converge-tangent routine %FOURIER Fourier/Least-Squares routine %EXPORT %END end of the input file %PATTERSON %JOB a caption is printed in the output %CONTINUE the program runs in default conditions from the last given command up to the end %STRUCTURE string this command is used to specify the name of the structure to investigate. The program creates the name of the files needed by adding the appropriate extension to the structure name. The file names are: string.bin - direct access file string.out - final coordinates file string.plt - file for graphics If this command is not used the default string "struct" (instead of the name of the structure) is used to create file names. %WINDOW [ x y ] graphic window is required. Optionally it is possible to increase the dimensions using x and y. Default values are 720,500. %NOWINDOW graphic window is suppressed %RESTART Fourier/Least-Squares restart routine
All commands and directives are in free format (between columns 1-80) and are case independent. Only the first four characters are significant.
The keywords can start in any position.If the first non-blank character is >, then the record is interpretated as a comment. SIR92 preserves intermediate results. For example, if invariant estimates have been already obtained during a previous run of SIR92, in a new run the commands
%INVARIANTS
Commands can be given in any order, with the following conditions:
- first routine used must be DATA, if it has not be used in a previous run; - INVARIANTS and SEMINV routines have no meaning if the diffraction moduli are not normalized; - PHASE routine has no meaning if no triplets have been calculated; - FOURIER routine cannot run before PHASE routine. - PSEUDO and PARTIAL directives require their own normalization. If one does not wish to use PSEUDO or PARTIAL information, then SIR92 must be restarted from %DATA command.The minimal information needed by SIR92 consists (see Example 1) of:
- cell parameters - cell content - space group symbol - reflections
The following limitations hold for commands and directives:
- PTEN cannot be used if the directive PSEUDO is on - SEMINV cannot be requested if PSEUDO is on - if PARTIAL is on, PSEUDO and RANDOM cannot be used - the directive SYMBOLS is of no use if RANDOM is on - PARTIAL and GENER are not compatible - PATTERSON followed by CONTINUE is not permitted