Truecell searches for more symmetric, higher symmetry cells that could be a "better" solution to powder indexing data. This can be useful where powder indexing programs favour small, low symmetry cells; and a higher volume, higher symmetry cell could be a better solution. Truecell can read *.SUM Summary results files generated by the Crysfire Powder Indexing Suite by Robin Shirley
CHEKCELL: Graphical Powder Indexing helper and Spacegroup Assignment Software has a version of Truecell included with it (accessible via the "Cell Parameters" window). Refer to the Chekcell tutorials for information involving Chekcell.
Truecell rules and logic
From: "Jean Laugier" [email@example.com] To: "Lachlan Cranswick" [firstname.lastname@example.org] Subject: Re: Chekcell and Truecell Date: Tue, 27 Nov 2001 15:11:21 +0100 1-If the "All" option is selected, all the solutions with a minimum monoclinic symetry is displayed. But in my opinion it is not a good thing, because a lot of low symetry solutions exists when the starting cell is cubic for example. 2-When the the "All" option is not selected, the program never searches the triclinic cells and verifies the following rules: -If the starting cell is cubic, only cubic multiple cells can be found. -If it is tetragonal, only tetragonal, hexagonal and rhomboedral cells can be found. -If it is orthorhombic, Truecell searches all cell kinds except monoclinic and triclinic. -If it is hexagonal, Truecell does not search orthorhombic, or monoclinic and triclinic. -If it is rhomboedral, Truecell does not search hexagonal cells, or monoclinic and triclinic. -If it is monoclinic, Truecell does not search triclinic cells. If the user's queries don't correspond to these rules an error message is displayed. It's a complicated, but I think it's logical. Cheers, Jean