GAMGI Interfaces: Cell Modify

# Cell Modify

- Symmetry
- Volume
- Position
- Origin
- View

Change here axes and node (0 0 0) for a single cell or a list of cells.

To modify an cell, click over its graphic image, or write its identification (name and number) on the Cell entry. To modify a list of cells, press the button List (after creating the list of cells with Cell->Select). Parameters for empty entries or Local choices remain unchanged.

To change an cell name write the new name in the Cell entry, followed by the cell number (GAMGI needs the number to identify the cell). To change the name for a list of cells, press List first and then write the new common name in the Name entry.

### O1, O2, O3

These entries provide the coordinates of the node in the lower-left corner of the cell where the new origin is, calculated with conventional or primitive cell vectors. When the lattice is primitive or vectors are primitive, this corner node becomes the new origin node (0 0 0) and no more coordinates are needed.

The cell position, given by the coordinates x,y,z of the origin node, is not affected by a change in the origin node, so the new origin node must occupy the position kept by the previous origin node, forcing a cell translation. The new cell origin can be outside the current cell volume.

### O4

When the lattice is centered and vectors are conventional, a fourth coordinate o4 is needed to point the new origin node (000) to one of the centered nodes. By default, o4 is 000, so no change is introduced. When the cell lattice is primitive P or the vectors defining the origin are primitive, that is the only possible value for o4. For I, C, F, R centered lattices, o4 can also take the values:

    I: 111
    C: 110
    F: 110, 101, 011
    R: 211, 122

corresponding to the numerators of the inner node coordinates, (1/2 1/2 1/2) for I lattices, (1/2 1/2 0) for C lattices, (0 1/2 1/2) (1/2 0 1/2) (1/2 1/2 0) for F lattices and (1/3 2/3 2/3) (2/3 1/3 1/3) for R lattices.

### Vectors

Indicate the type of cell vectors, Conventional or Primitive, used to determine the node with o1, o2, o3 coordinates, as described above. When o4 is not 000, a centered cell is involved and Vectors must be Conventional.

### Axes

Controls whether cell axes are visible. Axes are positioned at node (0 0 0), and can be represented either by conventional or by primitive vectors. The three axes use the rgb color scheme: red for the first axis, green for the second and blue for the third.

### Vectors

Indicate the type of cell vectors to show, Conventional or Primitive. These are totally independent of the vectors used to indicate the node (0 0 0).
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