CELL
This is part of the colvar module

Calculate the components of the simulation cell

Description of components

By default this Action calculates the following quantities. These quanties can be referenced elsewhere in the input by using this Action's label followed by a dot and the name of the quantity required from the list below.

Quantity Description
ax the ax component of the cell matrix
ay the ay component of the cell matrix
az the az component of the cell matrix
bx the bx component of the cell matrix
by the by component of the cell matrix
bz the bz component of the cell matrix
cx the cx component of the cell matrix
cy the cy component of the cell matrix
cz the cz component of the cell matrix
Options
NUMERICAL_DERIVATIVES

( default=off ) calculate the derivatives for these quantities numerically

Examples
The following input tells plumed to print the squared modulo of each of the three lattice vectors
cell: CELL
aaa:    COMBINE ARG=cell.ax,cell.ay,cell.az POWERS=2,2,2 PERIODIC=NO
bbb:    COMBINE ARG=cell.bx,cell.by,cell.bz POWERS=2,2,2 PERIODIC=NO
ccc:    COMBINE ARG=cell.cx,cell.cy,cell.cz POWERS=2,2,2 PERIODIC=NO
PRINT ARG=aaa,bbb,ccc
(See also COMBINE and PRINT).