Erratum to: CONTENT OF THE ISSUE 2 (2022)

Journal of Structural Chemistry - An Erratum to this paper has been published: https://doi.org/10.1134/S0022476622040205     

A Composite of Complex and Chemical Hydrides Yields the First Al‐Based Amidoborane with Improved Hydrogen Storage Properties

The first Al‐based amidoborane Na[Al(NH₂BH₃)₄] was obtained through a mechanochemical treatment of the NaAlH₄–4 AB (AB=NH₃BH₃) composite releasing 4.5 wt % of pure hydrogen. The same amidoborane was also produced upon heating the composite at 70 °C. The crystal structure of Na[Al(NH₂BH₃)₄], elucidated from synchrotron X‐ray powder diffraction and confirmed by DFT calculations, contains the previously unknown tetrahedral ion [Al(NH₂BH₃)₄]^?, with every NH₂BH₃^? ligand coordinated to aluminum through nitrogen atoms. Combination of complex and chemical hydrides in the same compound was possible due to both the lower stability of the Al?H bonds compared to the B?H ones in borohydride, and due to the strong Lewis acidity of Al³⁺. According to the thermogravimetric analysis–differential scanning calorimetry–mass spectrometry (TGA–DSC–MS) studies, Na[Al(NH₂BH₃)₄] releases in two steps 9 wt % of pure hydrogen. As a result of this decomposition, which was also supported by volumetric studies, the formation of NaBH₄ and amorphous product(s) of the surmised composition AlN₄B₃H_(0–3.6) were observed. Furthermore, volumetric experiments have also shown that the final residue can reversibly absorb about 27 % of the released hydrogen at 250 °C and p(H₂)=150 bar. Hydrogen re‐absorption does not regenerate neither Na[Al(NH₂BH₃)₄] nor starting materials, NaAlH₄ and AB, but rather occurs within amorphous product(s). Detailed studies of the latter one(s) can open an avenue for a new family of reversible hydrogen storage materials. Finally, the NaAlH₄–4 AB composite might become a starting point towards a new series of aluminum‐based tetraamidoboranes with improved hydrogen storage properties such as hydrogen storage density, hydrogen purity, and reversibility.     

Complexes of N-thiophosphorylthioureas (HL) with copper(I). Crystal structures of [Cu3L3] and [Cu(PPh3)2L] chelates

Reaction of the potassium salts of N-thiophosphorylated thioureas of common formula RC(S)NHP(S)(OiPr)(2) [R = morpholin-N-yl (HL(a)), piperidin-N-yl (HL(b)), NH(2) (HL(c)), PhCH(2)NH (HL(d))] with Cu(PPh(3))(3)I in aqueous EtOH/CH(2)Cl(2) leads to mononuclear [Cu(PPh(3))(2)L-S,S'] complexes. Using copper(i) iodide instead of Cu(PPh(3))(3)I, polynuclear complexes [Cu(n)(L-S,S')(n)] were obtained. The structures of these compounds were investigated by ES-MS, elemental analyses, 1H and 31P NMR in solution, IR and 31P solid-state MAS NMR spectroscopy. The crystal structures of [Cu(3)L(3)(a)] and [Cu(PPh(3))(2)L(b)] were determined by single-crystal X-ray diffraction.     

Unravelling the origin of intermolecular interactions using absolutely localized molecular orbitals

An energy decomposition analysis (EDA) method is proposed to isolate physically relevant components of the total intermolecular interaction energies such as the contribution from interacting frozen monomer densities, the energy lowering due to polarization of the densities, and the further energy lowering due to charge-transfer effects. This method is conceptually similar to existing EDA methods such as Morokuma analysis but includes several important new features. The first is a fully self-consistent treatment of the energy lowering due to polarization, which is evaluated by a self-consistent field calculation in which the molecular orbital coefficients are constrained to be block-diagonal (absolutely localized) in the interacting molecules to prohibit charge transfer. The second new feature is the ability to separate forward and back-donation in the charge-transfer energy term using a perturbative approximation starting from the optimized block-diagonal reference. The newly proposed EDA method is used to understand the fundamental aspects of intermolecular interactions such as the degree of covalency in the hydrogen bonding in water and the contributions of forward and back-donation in synergic bonding in metal complexes. Additionally, it is demonstrated that this method can be used to identify the factors controlling the interaction of the molecular hydrogen with open metal centers in potential hydrogen storage materials and the interaction of methane with rhenium complexes.     

Nonlinear Resonance upon the Excitation of a Magnetic Nanocylinder by a Spin-Polarized Current

JETP Letters - A nonlinear resonance excited by an alternating spin-polarized current in a ferromagnetic nanocylinder whose magnetization comprises a magnetic vortex is studied theoretically. The...     

Formation of 1,2,4-oxadiazoles in the course of photooxidation of aromatic azides in acetonitrile

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Photochemically Induced Circular Dichroism of Semiconductor Nanocrystals

Optics and Spectroscopy - Here, we report an investigation of optical activity which was photochemically induced by illumination of QRs and DiRs with circularly polarized light; the photo-induced...