Employing multiscale in silico modeling, we propose switching molecular diodes on the basis of endohedral fullerenes (fullerene switching diode, FSD), encapsulated with polar molecules of general type MX (M: metal, X: nonmetal) to be used for data storage and processing. Here, we demonstrate for MX@C70 systems that the relative orientation of enclosed MX with respect to a set of electrodes connected to the system can be controlled by application of oriented external electric field(s). We suggest systems with two- and four-terminal electrodes, in which the source and drain electrodes help the current to pass through the device and help the switching between the conductive states of FSD via applied voltage. The gate electrodes then assist the switching by effectively lowering the energy barrier between local minima via stabilizing the transition state of switching process if the applied voltage between the source and drain is insufficient to switch the MX inside the fullerene. Using nonequilibrium Green’s function combined with density functional theory (DFT-NEGF) computations, we further show that conductivity of the studied MX@C70 systems depends on the relative orientation of MX inside the cage with respect to the electrodes. Therefore, the orientation of the MX inside C70 can be both enforced (“written”) and retrieved (“read”) by applied voltage. The studied systems thus behave like voltage-sensitive switching molecular diodes, which is reminiscent of a molecular memristor.

A recent study (Sci. Adv. 2017, 3, e1602833) has shown that FH⋅⋅⋅OH hydrogen bond in a HF⋅H O pair substantially shortens, and the H-F bond elongates upon encapsulation of the cluster in C fullerene. This has been attributed to compression of the HF⋅H O pair inside the cavity of C . Herein, we present theoretical evidence that the effect is not caused by a mere compression of the H O⋅HF pair, but it is related to a strong lone-pair-π (LP-π) bonding with the fullerene cage. To support this argument, a systematic electronic structure study of selected small molecules (HF, H O, and NH ) and their pairs enclosed in fullerene cages (C , C , and C ) has been performed. Bonding analysis revealed unique LP-π interactions with a charge-depletion character in the bonding region, unlike usual LP-π bonds. The LP-π interactions were found to be responsible for elongation of the H-F bond. Thus, the HF appears to be more acidic inside the cage. The shortening of the FH⋅⋅⋅OH contact in (HF⋅H O)@C originates from an increased acidity of the HF inside the fullerenes. Such trends were also observed in other studied systems.

Actinide–actinide bonds are rare. Only a few experimental systems with An–An bonds have been described so far. Recent experimental characterization of the U2@I h (7)-C80 (J. Am. Chem. Soc. 2018, 140, 3907) system with one-electron two-center (OETC) U–U bonds as was predicted by some of us (Phys. Chem. Chem. Phys. 2015, 17, 24182) encourages the search for more examples of actinide–actinide bonding in fullerene cages. Here, we investigate actinide–actinide bonding in An2@D 5h (1)-C70, An2@I h (7)-C80, and An2@D 5h (1)-C90 (An = Ac–Cm) endohedral metallofullerenes (EMFs). Using different methods of the chemical bonding analysis, we show that most of the studied An2@C70 and An2@C80 systems feature one or more one-electron two-center actinide–actinide bonds. Unique bonding patterns are revealed in plutonium EMFs. The Pu2@I h (7)-C80 features two OETC Pu–Pu π bonds without any evidence of a corresponding σ bond. In the Pu2@D 5h (1)-C90 with r Pu–Pu = 5.9 Å, theory predicts the longest metal–metal bond ever described. Predicted systems are thermodynamically stable and should be, in principle, experimentally accessible, though radioactivity of studied metals may be a serious obstacle.

Endohedral fullerenes with a dipolar molecule enclosed in the fullerene cage have great poten-tial in molecular electronics, such as diodes, switches, or molecular memristors. Here, we study a series of...

Phospho(i)nate derivatives of dipicolylamine show excellent selectivity for Zn(ii) over alkaline earth metal ions.

In this paper, an in silico proof of concept of a spinristor is proposed and provided; a new electronic component that combines a spin-filter and a memristor in a single molecule, useful for in-memory processing. It builds on the idea of an open-shell transition metal ion enclosed within an elliptical fullerene connected to a pair of electrodes. The spin-and electronic-polarization induced by the enclosed open-shell metallic ion leads to differential rectification of the electrons at low voltages applied between the source-drain electrodes, V SD . The position of the encapsulated ion can be switched by a high V SD which leads to a change in the direction of the rectification and the spin-filtering ratio. The system can thus be used as a switching rectifier, that is, a memristor and a spin-filter; therefore, a spinristor. The effect of different linkers on the function of the proposed device is further analyzed to show that linkers reduce the overall conductivity by an order of magnitude, but improve the spin-filtering ratio. The computations suggest that nitrile and isocyanide linkers enhance the rectification, too. To the best of the authors' knowledge, spinristor has no macroscopic counterpart in electronics, so far.

Hydrogen carriers, such as hydrazine (N2H4), may facilitate long duration energy storage, a vital component for resilient grids by enabling more renewable energy generation. Lanthanide coordination chemistry with N2H4 as well as efforts to displace N2H4 from the metal coordination sphere to develop an efficient catalytic production cycle were detailed. Modeling the equilibrium of different ligand coordination, it was predicted that strong sigma donor molecules would be required to displace N2H4. Monitoring competition experiments with nuclear magnetic resonance confirmed that trimethyl phosphine oxide, dimethylformamide, and dimethyl sulfoxide displaced N2H4 in large or small lanthanide complexes.

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