Multidimensional organization of heteromolecules by robust DNA motifs

A two dimensional polynucleic acid array of polygonal units linked together by complementary double cohesive ends, comprising a plurality of polygonal units, wherein:

• each of said polygonal units has, as edges, parallel helices of connected nucleic acid multi-crossover domains along their helix axes;
• each of at least two said edges of each of said polygonal units has ends with two parallel double helices;
• each of said two parallel double helices terminate in a cohesive end to provide a double cohesive end at each end of said at least two edges, whereby said double cohesive end of one edge of a polygonal unit is cohered to a complementary double cohesive end of an adjacent polygonal unit in the array to form an extended edge linking together two adjacent polygonal units;
• and
• at least one edge, which is different from said at least two edges, of a subset of said polygonal units has at least one end which is attached to a nanoparticle or pendant molecule.