Meaning of aLCV. Two generic unit cells are represented in this figure. The three diagonals along each one of the three main unit cell's faces depend both on the cell's sides and the cell's angles. Any of the diagonals in one of the two cells will be, in general, different from the corresponding diagonals in the other cell. Let's call Δa, Δb, Δc the difference between corresponding diagonals. The aLCV (absolute Linear Cell Variation) for the group formed by the two unit cells is the maximum difference: aLCV = max(Δa, Δb, Δc). When more crystals are added, the aLCV is recalculated as before, considering all pairs of unit cells, and selecting the highest of all maximum values computed as the new aLCV.