Interpenetration is an intrinsic behaviour for the porous coordination networks. To prevent the interpenetration, a common strategy is the imposition of geometric or steric restrictions by incorporating bulky moieties into organic tectons. So far, most of the available incorporations have been achieved through a covalent connection, while few involved in the non-covalent weak interactions. In this paper, we have reported that such interpenetration can be prevented by the less common lone pair-π interactions. By imposing the lone pair-π interactions through the addition of lone-pair-bearing N-methylpyrrolidin-2-one or iodine, combinations of rigid naphthalene diimide tectons bearing two divergently oriented pyridyl units at both imide extremities with ZnSiF6 led to non-interpenetrated cuboid 3-D coordination networks that should have been interpenetrated. In addition, such close-contacting lone pair-π interactions between electron donors and acceptors have also been demonstrated to play a key role in their photochromic properties.

The search for high-performance electrode materials in organic rechargeable batteries remains a key challenge. Reported herein is a molecular structural modification of perylene imides, a promising class of redox-active electrode materials, for improved battery performance. The Diels-Alder extension of perylene imides at the lateral position led to the simultaneous incorporation of two electron-withdrawing carbonyl groups and extension of the π system, which is supposed to favor high specific capacity, operating voltage, and electronic conductivity. After the chiral dimerization of the extended species with 1,2-diaminocyclohexane, it was anticipated that the porosity and coulombic interactions with lithium ions would be promoted, which would be beneficial for fast reaction kinetics and long cycling life. As expected, in lithium batteries, the obtained chiral and π-extended tweezer, which features six imide groups and a porous solid-state network of 42.2 % accessible cell volume, was found to deliver a reversible capacity of 92.1 mA h g at a charge/discharge rate of 1 C within an operating voltage window of 1.60-2.80 V versus Li /Li, around 75 and 50 % of which was maintained after 100 and 300 galvanostatic cycles, respectively, much better than those of unmodified species.

Metal-ion-directed assembly of naphthalene diimide tectons cooperatively enhanced by anion-π interactions of giant anions, PMo12O40(3-), leads to a novel organic-inorganic hybrid with ultrafast-responsive photochromic properties, which is attributed to the polyoxometalate-sensitized photo-induced radical generation of naphthalene diimide units.

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Nonadiabatic interactions in the NeICl van der Waals complex have been explored in the lowest energy triad of ICl ion-pair states (∼39 000 cm−1). Dispersed fluorescence measurements reveal emission characteristic of multiple ion-pair electronic states, with the relative contributions from the E(0+), β(1), and D′(2) states changing with the initial ICl vibrational excitation (vICl). Emission directly from NeICl (vICl=0) complexes indicates that the initially prepared NeICl levels have mixed electronic character and that the ICl electronic parentage changes with the initial van der Waals vibrational level selected. NeICl complexes prepared with 1–4 quanta of ICl stretch undergo rapid vibrational predissociation with a strong propensity for ΔvICl=−1 relaxation. The electronic state(s) populated in the ICl fragments differ from the mixed electronic character of the initially prepared level, demonstrating that vibrational predissociation is accompanied by nonadiabatic electronic state changing processes. The observed final state selectivity may be attributed to the relative strength of the nonadiabatic couplings between the initial NeICl bound state and the final ICl states or a momentum gap rationale based on the overlap between the NeICl bound state wave function and the highly oscillatory continuum wave function of the separating fragments.