Hi,
I was trying to use SHELXD to solve peptide structure. But I got stuck in the input .ins file, and I need some advice.
In the .ins file,
TITLE
CELL
ZERR
LATT
SYMM
SFAC C H N O
UNIT
FIND
PLOP
NTRY
HKLF
END
A rough estimate, there will be 62 C, 122 H, 14 N, 32 O in one unit cell.
1 for UNIT command, should the following nums be the num of atoms(C H N O) per unit cell and multiplied by 4? 62x4 for C, 122x4 for H, etc?
2 for FIND, the manual says 'estimated num of sites within 20% of true number', so should it be 20% of the total number of atoms in one unit cell? (62＋122＋14＋32)x 20%?
3 for PLOP, the manual says '# of peaks to start with in each cycle, Peaks are then eliminated one at a time until either the correlation coefficient cannot be increased any more or 50% of the peaks have been eliminated' & 'one should specify more than the expected number of atoms because this procedure involves the elimination of the 'wrong' atoms' which I don't fully understand, should the following nums be bigger than the total num of atoms in one unit cell?
Thanks in advance!
Lu
