Conventional cells: monoclinic I- and C-centered cells.
In the selection of a centered cell in the monoclinic system, it is recommended that the experimentalist select an I-centered cell for those cases in which it is the conventional cell - cases in which a and c are coincident with the shortest two translations in the net perpendicular to b (b-axis unique). The common practice of selecting a non-conventional C-centered cell in such cases should be discontinued.
Mighell
Alan D
AD
Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899-8520, USA. alan.mighell@nist.gov