Supramolecular Assembly Based on the Rosette Motif

1 Anionic Rosette Ribbon Built of Guanidinium and Hydrogen Carbonate Dimer 

Each supramolecular rosette comprises a quasihexagonal assembly of two GM+ and four HC units connected by strong Nqm-H- -Ohc and Ohc-H- -Ohc hydrogen bonds. The (HC )2 dimer is shared as a common edge of adjacent rosettes and makes full use of its remaining acceptor sites in linking with GM+. However, each GM+ in 

2 Anionic Rosette Networks Assembled with Guanidinium and Ca-symmetric Oxo-anion Building Blocks 

Carbonate C(2) and guanidinium C(l) both have site symmetry m and are connected pairwise through charge-assisted N+-H- -0 hydrogen bonds of about 2.80 A to form motif [D]. Notably, motifs [C] and [D] are linked together in two ways by pairs of Oba-H- -OcB (2.56 and 2.59 A) or -Oba (2.89 and 2.93 A) hydrogen bonds 

The mean atomic deviation from the mean plane is 0.12 and 0.29 A for rosettes [A] and [B], respectively. The dihedral angle between [A] and [B] is about 24.3°, which reflects the wavy characteristics of the rosette layer. 

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