The crystallographic problems of two-dimensional crystal, such as the matrix expression, the symmetry and the systematic absence law of the crystal's X-ray diffraction, are studied.

The Global Plan includes a large budget for ACSM but, in the absence of systematic guidance in 2006 (to be published in 2007), NTP budgets were typically small and activities uneven.

In the absence of systematic upsetting instructions, we would waste quite a few materials as well as a great deal of time for model experimenting.