Platinum(<Emphasis Type="SmallCaps">iv</Emphasis>)-mediated nucleophilic addition of 1,3-diphenylguanidine to propiononitrile

The reaction of the trans-[PtCl₄(EtCN)₂] complex with diphenylguanidine (DPG) in a molar ratio of 1: 2 proceeds via the nucleophilic addition of DPG to coordinated nitrile and the coordination of DPG to the metal center to form the [PtCl₄{NH=C(NHPh)₂}{NH=C(Et)-N=C(NHPh)₂}] complex with the open-chain 1,3,5-triazapentadiene ligand. The latter undergoes chelation in solution (84 h, 50 °C, CDCl₃), and the ring closure is accompanied by the replacement of the coordinated chloride and the formation of the cationic complex [PtCl₃{NH=C(NHPh)₂}{NH=C(Et)NHC(NHPh)=NPh}](Cl). The reaction of the trans-[PtCl₄(EtCN)₂] complex with DPG in a molar ratio of 1: 4 affords the [PtCl₃{NH=C-(NHPh)₂}{NH=C(Et)NC(NHPh)=NPh}] complex with the chelating 1,3,5-triazapentadienate ligand.     

Electron–nuclear motions in a series of meta-substituted iodobenzene derivatives as probed by <Superscript>127</Superscript>I NQR

A relation between the quadrupole coupling constant e ² Qq _zz and asymmetry parameter η has been found for a series of meta-substituted iodobenzene derivatives. The relationships e ² Qq _zz(η) for electrondonor and electron-acceptor substituents have the same form but different numerical values of parameters. The average time of full electron transfer via tunneling has been evaluated.     

PROPIOLATE CLUSTER COMPLEXES (Bu4N)2[Mo6X8(OOC–C≡CH)6] (X = Br,I)

Journal of Structural Chemistry - Two new cluster complexes (Bu4N)2[Mo6X8(OOC–C≡CH)6] (1) (X&nbsp;=&nbsp;Br) and (2) (X&nbsp;=&nbsp;I) are synthesized by the reaction of...     

WS2/MoS2 Heterostructures through Thermal Treatment of MoS2 Layers Electrostatically Functionalized with W3S4 Molecular Clusters

The preparation of 2D stacked layers combining flakes of different nature gives rise to countless numbers of heterostructures where new band alignments, defined at the interfaces, control the electronic properties of the system. Among the large family of 2D/2D heterostructures, the one formed by the combination of the most common semiconducting transition metal dichalcogenides, WS₂/MoS₂, has awakened great interest owing to its photovoltaic and photoelectrochemical properties. Solution as well as dry physical methods have been developed to optimize the synthesis of these heterostructures. Here, a suspension of negatively charged MoS₂ flakes is mixed with a methanolic solution of a cationic W₃S₄-core cluster, giving rise to a homogeneous distribution of the clusters over the layers. In a second step, a calcination of this molecular/2D heterostructure under N₂ leads to the formation of clean WS₂/MoS₂ heterostructures, where the photoluminescence of both counterparts is quenched, proving an efficient interlayer coupling. Thus, this chemical method combines the advantages of a solution approach (simple, scalable, and low-cost) with the good quality interfaces reached by using more complicated traditional physical methods.     

Observation of Coherent Population Trapping in Ensembles of Diamond NV-Centers under Ground-State Level Anticrossing Conditions

Optics and Spectroscopy - The coherent population trapping effect in ensembles of diamond NV-centers under ground-state level anticrossing conditions was implemented with the application of a...     

A characterization of a minimax test in the problem of testing two composite hypotheses

We obtain a characterization of a minimax test in the problem of testing two composite hypotheses via a solution of a dual problem. In comparison to previous results, our characterization is valid under much weaker assumptions, which became possible, in particular, due to a modification of a dual problem.     

Thermodynamic characteristics of triphenylantimony diacrylate

The heat capacity of triphenylantimony diacrylate Ph₃Sb(O₂CCH=CH₂)₂ was studied in an adiabatic vacuum calorimeter at 6?C350 K and differential scanning calorimeter at 330?C450 K. Melting was revealed at these temperatures; the melting point was estimated at 428.4 ± 0.5 K. It was accompanied by the partial decomposition of the substance. The low-temperature (20 K ?? T ?? 50 K) heat capacity was treated using the Debye theory of the heat capacity of solids and its multifractal model. The type of the structure topology was determined. The standard thermodynamic functions C _p ^o (T), H ^o(T) ? H ^o(0), S ^o(T), and G ^o(T) ? H ^o(0) of the compound in the crystal state were calculated from the obtained experimental data in the range from T ?? 0 to 428 K. The standard entropy of the formation of the crystalline compound Ph₃Sb(O₂CCH=CH₂)₂ at T = 298.15 K was determined.     

Magnetic and magnetooptical properties of multilayer ferromagnet-semiconductor nanostructures

The magnetic and magnetooptical properties of spin-tunneling multilayer permalloy-silicon carbide nanoheterostructures deposited by rf sputtering have been studied. Magnetometric and magnetooptical methods are used to show that the magnetic-semiconducting nanostructures have a complex magnetic structure and to track the evolution of the magnetic properties of these structures as functions of the magnetizing field and the thickness and sequence order of ferromagnetic and semiconducting layers in them. The induction response and the field and orientation dependences of the transversal Kerr effect are found to have anomalies. The experimental results are interpreted under the assumption that there is exchange interaction between the ferromagnetic and semiconducting layers through a thin magnetically ordered transition layer formed inside the interface.