Flexible porous coordination polymers change their structure in response to molecular incorporation but recover their original configuration after the guest has been removed. We demonstrated that the crystal downsizing of twofold interpenetrated frameworks of [Cu(2)(dicarboxylate)(2)(amine)](n) regulates the structural flexibility and induces a shape-memory effect in the coordination frameworks. In addition to the two structures that contribute to the sorption process (that is, a nonporous closed phase and a guest-included open phase), we isolated an unusual, metastable open dried phase when downsizing the crystals to the mesoscale, and the closed phase was recovered by thermal treatment. Crystal downsizing suppressed the structural mobility and stabilized the open dried phase. The successful isolation of two interconvertible empty phases, the closed phase and the open dried phase, provided switchable sorption properties with or without gate-opening behavior.

Metal-organic frameworks (MOFs) as well as porous coordination polymers (PCPs) are porous, organic-inorganic hybrid solids with zeolite-like structures and properties. Due to their extraordinarily high surface area and well defined pore structure MOFs can be used for the stabilization of metal nanoparticles with adjustable size. The embedded metal nanoparticles are still accessible for other reagents due to the high porosity of the MOF systems. This fact makes "metal@ MOF" systems especially interesting for heterogeneous catalysis, gas storage and chemical sensing. This review compiles the cases of metal nanoparticles supported by or embedded into MOFs reported so far and the main aspects and

The progressive liquid-phase layer-by-layer (LbL) growth of anisotropic multicomponent layer-based porous coordination polymers (PCPs) of the general formula [M(L)(P)(0.5)] (M: Cu(2+), Zn(2+); L: dicarboxylate linker; P: dinitrogen pillar ligand) was investigated by using either pyridyl- or carboxyl-terminated self-assembled monolayers (SAMs) on gold substrates as templates. It was found that the deposition of smooth, highly crystalline, and oriented multilayer films of these PCPs depends on the conditions at the early growth cycles. In the case of a two-step process with an equimolar mixture of L and P, growth along the [001] direction is strongly preferred. However, employing a three-step scheme with full separation of all components allows deposition along the [100] direction on carboxyl-terminated SAMs. Interestingly, the growth of additional layers on top of previously grown oriented seeding layers proved to be insensitive to the particular growth scheme and full retention of the initial orientation, either along the [001] or [100] direction, was observed. This homo- and heteroepitaxial LbL growth allows full control over the orientation and the layer sequence, including introduction of functionalized linkers and pillars.

Besides conventional approaches for regulating in-coming molecules for gas storage, separation, or molecular sensing, the control of molecular release from the pores is a prerequisite for extending the range of their application, such as drug delivery. Herein, we report the fabrication of a new porous coordination polymer (PCP)-based composite consisting of a gold nanorod (GNR) used as an optical switch and PCP crystals for controlled molecular release using light irradiation as an external trigger. The delicate core-shell structures of this new platform, composed of an individual GNR core and an aluminum-based PCP shell, were achieved by the selective deposition of an aluminum precursor onto the surface of GNR followed by the replication of the precursor into aluminum-based PCPs. The mesoscopic structure was characterized by electron microscopy, energy dispersive X-ray elemental mapping, and sorption experiments. Combination at the nanoscale of the high storage capacity of PCPs with the photothermal properties of GNRs resulted in the implementation of unique motion-induced molecular release, triggered by the highly efficient conversion of optical energy into heat that occurs when the GNRs are irradiated into their plasmon band. Temporal control of the molecular release was demonstrated with anthracene as a guest molecule and fluorescent probe by means of fluorescence spectroscopy.