Atoms/Bonds - Global, Which Atoms/Bonds Tab
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Dialog Box Tab - called from: Input1 Menu

This tab specifies which atoms will be changed: it applies to input atoms, not generated atoms. You can change parameters for all atoms, for all atoms of a given type, for a sequence of atoms, or for all atoms in a given fragment (if there is more than one fragment - see Multiple Structures ) in the Transform menu. You can also change parameters for all bonds.

Randomize. This allows you to modify only a certain fraction of the input atoms chosen, on a random basis. This is intended primarily for representing solid solutions - you can modify the colors and/or sizes of individual input atoms. Before doing this, it will normally be necessary to do the Generated to Input option in the Transform Menu, so that all atoms become input atoms. If only atoms on a certain site are to be modified, it may be necessary to change the atom type of this site before transforming Generated to Input.

A solid solution with only two types of atom is straightforward, but more than two occupants will require some pre-calculation and repeated use of this dialog. Since all atoms present are affected, the fraction which is entered in this dialog must be with respect to the new occupant and those occupants already present, not the final fraction. For example, suppose you want to show four occupants, each with occupancy factor 0.25. The first occupant is already present. When adding the second occupant, for example changing the color, the fraction should be 0.5, because this gives the correct ratio of occupant 1 and 2. To add the third component, this dialog must be repeated and the fraction is 0.3333, and for the fourth and last occupant the fraction is 0.25.

Select the variables or attributes to be changed in the Variables Tab.