CRYSTALLOGRAPHIC ASPECTS OF MINIMAL SURFACES

Symmetry properties of 3-periodic minimal surfaces subdividing R3 into two congruent regions are discussed. The relation between the order of a flat point and its site symmetry is established. Explicit formulae are given for the calculation of the genus of such a surface depending on the kind of surface patches that build up the surface. Making use of 2-fold axes that have to be embedded in a surface with given symmetry new families of minimal balance surfaces have been derived. Corresponding lists are referred to the different kinds of surface patches