Understanding the Role of Helical Chains in the Formation of Noncentrosymmetric Solids

Packing of Helices: Is Chirality the Highest Crystallographic Symmetry?

“…From the investigation of these compounds, we emphasized that the packing of helices with opposite handedness does not allow equivalent bridging of the helices. Thus, the packing of helices is also dependent on their symmetries but independent of the system (millimeter-sized helical drill bits, proteins, helical polymers, organic or inorganic structure) or the nature of interactions (capillary forces [15], close-packing of proteins [14,17], covalent [18], or entropic [16]). …”

Coordination Polymers and Metal Organic Frameworks Derived from 1,2,4-Triazole Amino Acid Linkers

“…But its electronic and structural asymmetry together with consolidated effort of noncovalent interactions with suitable metal ions as connectors may lead to crystallization in a non-centrosymmetric space group. By using bridging ligands with a significant kink in the topology instead of linear rigid molecules, the formation of networks with a lower symmetry and helicity is possible [80,108]. The spontaneous helicity observed in 3 is due to the hierarchical self-assembly of the tiny synthon HL1 originating in non-centrosymmetric space group which falls into this category.…”

Preparation, Structure, and Second‐order Nonlinear Optical Properties of a Borate‐Carboxylic Acid Compound: NH4B[d‐(+)‐C4H4O5]2·H2O

“…[1][2][3][4][5][6][7][8][9][10][11] Several NLO crystals, which have largely satisfied the practical requirements in the UV and visible regions have been found, such as β-BaB 2 O 4 (BBO), [12] KTiOPO 4 (KTP), [13] and LiB 3 O 5 (LBO). [14] However, they also have shortcomings of one kind or another, which has limited their applications.…”

“…The overall reactions are shown in Equations (1) and (2). Stability constants for BX -complex formation (K 1 ) increase as the acidity of the ligand increases.…”