Liquid Organic Frameworks: The Single Network Plumbers Nightmare Bicontinuous Cubic Liquid Crystal, S. Poppe (a), X. Cheng (a,b), C. Cheng (c), X.B. Zeng (d), F. Liu (c), G. Ungar (c,d)
and C. Tschierske (a), J. Am. Chem. Soc. 142, 3296-3300 (2020); http://doi. org/10.1021/jacs.9b11073. (a) Martin-Luther-University Halle- Wittenberg, Halle (Germany)
(b) Yunnan University, Kunming (China) (c) Xi an Jiaotong University, Xi an (China) (d) University of Sheffield, Sheffield (UK)
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PRINCIPAL PUBLICATION AND AUTHORS
filling with increasing radius of the cylindrical network segments. For infinite parallel columns (columnar phase) dV/dr increases linearly, but for this the volume of the side chains must fan out to fill the space, ideally being dendritic. Failing that, networks with 3-, 4- or even 6-way junctions present the alternative, since they require less divergent chains. Even so, the compounds giving the rod-bundle DG  and DD  were still branched, though shorter for DD. However the tight SP network with 6-way junctions does not require the chains to fan out much, hence the chains in the current compounds are linear, but still long enough to reach points distant from the network where the 6-way curve drops to 0. To engineer the last remaining unrealised Cubbi in TLCs, the DP, these side-chains will need to be short, as dV/dr à 0 early.
Fig. 64: Artist s impression of several unit cells of the SP Pm 3m phase. Green ellipsoids are aromatic cores with blue polar end-groups. Side chains are omitted
for clarity. Molecular formulae are also given.