A D3Rank3Tensor is a third rank tensor with
D3 point group symmetry. The arguments d11 and
d14 are real numbers. The first integer in
each argument name is a space index (1, 2, or 3) and the second is
a Voigt index (1 through 6).
Figure 6.139. Structure of a D3 Third Rank Tensor
Structure of a D3 rank 3 tensor. For an explanation of
the symbols, see Figure 6.57.