SHELX C/D/E: Difference between revisions

88 bytes added ,  24 September 2011
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  shelxc xx <t
  shelxc xx <t
which would read the instructions from the file t and write the files xx.hkl (h,k,l,I,&sigma;(I) in SHELX HKLF4 format for density modification by SHELXE), xx_fa.ins (cell, symmetry etc. for heavy atom location using SHELXD) and xx_fa.hkl (h,k,l,F<sub>A</sub>,&sigma;(F<sub>A</sub>),&alpha; for both SHELXD and SHELXE). The starting phases for density modification are estimated as (heavy atom phase + &alpha;) in the simplified approach used by SHELXE, &alpha; is calculated by SHELXC from the anomalous and dispersive differences. For SAD &alpha; is 90º (I<sub>+</sub> > I<sub>–</sub>) or 270º (I<sub>+</sub> < I<sub>–</sub>), for SIR and RIP &alpha; is 0º or 180º and for SIRAS or MAD &alpha; may be anywhere in the range 0º to 360º.  
which would read the instructions from the file t and write the files xx.hkl (h,k,l,I,&sigma;(I) in SHELX HKLF4 format for density modification by SHELXE), xx_fa.ins (cell, symmetry etc. for heavy atom location using SHELXD) and xx_fa.hkl (h,k,l,F<sub>A</sub>,&sigma;(F<sub>A</sub>),&alpha; for both SHELXD and SHELXE). The starting phases for density modification are estimated as (heavy atom phase + &alpha;) in the simplified approach used by SHELXE, &alpha; is calculated by SHELXC from the anomalous and dispersive differences. For SAD &alpha; is 90º (I<sub>+</sub> > I<sub>–</sub>) or 270º (I<sub>+</sub> < I<sub>–</sub>), for SIR and RIP &alpha; is 0º or 180º and for SIRAS or MAD &alpha; may be anywhere in the range 0º to 360º.  
<p>The above command line could be used under UNIX or Windows; under UNIX the commands to run SHELXC, SHELXD and SHELXE and the instructions for SHELXC may also be combined into a single script file as shown in the following examples. In these scripts, the instructions start on the line after '<<EOF' and are terminated by 'EOF'. The instructions may be given in any order; CELL (unit-cell), SPAG (space group in PDB notation, spaces are ignored) and FIND (followed by the number of heavy atoms) must be given; the optional instructions SFAC, MIND, NTRY, SHEL, ESEL and DSUL, if present, are copied to the SHELXD input file. <br><br>
<p>The above command line could be used under UNIX or Windows; under UNIX the commands to run SHELXC, SHELXD and SHELXE and the instructions for SHELXC may also be combined into a single script file as shown in the following examples. In these scripts, the instructions start on the line after '<<EOF' and are terminated by 'EOF'. The instructions may be given in any order; CELL (unit-cell), SPAG (space group in PDB notation, spaces are ignored) and FIND (followed by the number of heavy atoms) must be given; the optional instructions SFAC, MIND, NTRY, SHEL, ESEL and DSUL, if present, are copied to the SHELXD input file.<br><br>
A beta-test version is currently [[SHELX_C/D/E#Obtaining_the_SHELX_programs|available]].


== SHELXD ==
== SHELXD ==
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