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Two noncentrosymmetric compounds, namely, [N-Bz-Py]2[Cu6I8] (1) and [N-Bz-Py]4[Ag9I13] (2) (N-Bz-Py(+) = N-benzylpyridinium), with three-dimensional open frameworks, were synthesized solvothermally via in situ benzylation of pyridine. 1 is constructed from 3-connected Cu3I7 secondary building units (SBUs) with chiral (10,3)-a topology, while the occluded N-Bz-Py(+) forms a complementary supramolecular (10,3)-a net via π-π interactions. 2 is characteristic of acentric connections of trimeric Ag3I8 and hexamer Ag6I12 SBU, while N-Bz-Py(+) in the channels aggregates into asymmetrically supramolecular chains via π-π interactions. Remarkable structural correlations imply the unique amplification and transfer of asymmetric information from V-shaped N-Bz-Py(+) to organic supramolecular nets and inorganic frameworks, which are confirmed by their second harmonic generation responses. Adsorption spectra reveal their semiconductive nature (2.52 eV for 1 and 3.02 eV for 2) and interesting reversible thermochromism for 1 based on the intermolecular charge transfer.

By using 1-methyl-4-(carbomethoxy)pyridinium (MCMP) as counterions, two iodoargentate hybrids, 1D [MCMP][AgI] (1) and 3D [MCMP][AgI] (2) have been synthesized and they exhibit rare electron transfer photochromism with a fast response rate, a wide response range and a long-lived charge-separated state in iodometallate systems. Noteworthily, the marked differences in the structure and photochromic performance of 1 and 2 are largely ascribed to the different aggregating behavior of electron-deficient MCMP counterions (C-HO hydrogen bonded trimer in 1 and π-π/C-Hπ chain in 2).

By employing in situ methylnicotinohydrazide dication (MNH(2+)) as an electron acceptor, we have constructed an iodocuprate(I) hybrid {[MNH][Cu2I3]2}n (1), which exhibits charge transfer (CT) thermochromism due to the intense absorption of CT and electron transfer (ET) photochromism with high photocoloration contrast and fast response to UV irradiation due to the synergetic effect of valence change of copper ions.

Two isostructural organic–inorganic hybrids are constructed from [Ag3I4]−/[Cu3I4]− chains and dimethylbenzotriazolium, which exhibit metal-dependent electronic behaviors and adjustable photoresponsive properties.

Matched with 3,5-bis(pyridine-2-yl)-1,2,4-triazole (2-bpt), a new electron donor-acceptor-based chlorobismuthate(III) hybrid, [2-bpt][BiCl(HO)]·5HO was prepared solvothermally and characterized. The title compound (hydrated form) and its dehydrated form exhibit photo- and thermo-induced intermolecular electron transfer (ET), which correspond to dual ET photo/thermochromism for hydrated form, charge transfer thermochromism during dehydration, and simultaneously photoluminescent responses, respectively.

Two iodoargentate hybrids, {[HNOM][AgI 2 ]•H 2 O} (1) and {[HINOM][AgI 2 ]•H 2 O} ( 2) (HNOM + = N-protonated 3-carbomethoxypyridinium; HINOM + = N-protonated 4-carbomethoxypyridinium), have been designed and prepared, which were constructed from typical [AgI 2 ] − inorganic chains and cationic hydrogen-bonding supramolecular networks (one-dimensional for 1 and threedimensional for 2) of lattice water and positional isomeric N-protonated carbomethoxypyridinium. Two hybrids exhibit sensitive photochromism based on intermolecular electron transfer (ET) and thermochromism due to reversible hydration and dehydration and the consequent variation of intermolecular charge transfer (CT). Furthermore, loss of lattice water gives rise to improved photochromic dehydrated form 1T and optically inert dehydrated form 2T, suggesting a delicate modulating effect of lattice contraction on the intermolecular CT and ET as well as consequently photoresponsive behaviors.