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A novel nitronyl nitroxide NIT-thien-3-Py (2-(3-(m-pyridyl)-2-thienyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) and its Mn(II) complex [Mn(hfac)2(NIT-thien-3-Py)]2 (hfac = hexafluoroacetylacetonate) have been obtained. X-ray analysis indicates that the Mn(II) complex possesses a cyclic dimer structure in which two radical ligands link two Mn(II) ions through their NO groups and pyridine rings. The study of the magnetic data indicates that the manganese(II) ion strongly and antiferromagnetically interacts with the directly bonding NO group and there is weak ferromagnetic coupling between two Mn–NO pairs through the thiophene and pyridine rings of the radical ligand in agreement with a spin polarization mechanism. [ABSTRACT FROM AUTHOR]

In the current research, the moisture-resistant of Mg-MOF-74 was successfully improved by coating with two-dimensional (2-D) hexagonal boron nitride (h -BN) during the facile hydrothermal synthesis process. Both TEM and SEM results revealed that 2-D h -BN is coated on Mg-MOF-74's surface. The crystal structure, morphology, surface area, thermal stability and CH 4 uptake capacity of Mg-MOF-74 were not drastically influenced by coating with h -BN as examined by XRD, FTIR, SEM, and TEM. Further, the coated Mg-MOF-74 demonstrated better stability than uncoated Mg-MOF-74, when being exposed to high humidity, in terms of surface area and CH 4 uptake capacity. It was observed that the coated Mg-MOF-74 with 1 ​wt % h -BN has reached to 1959 ​m2 ​g−1 surface area and CH 4 uptake capacity of 43 ​cm3 ​g−1 after exposure to high humidity for a duration of 1 month. Thus, this research work has opened a new window towards the improvement of the water stability of Mg-MOF-74. [Display omitted] • The water resistance capacity of Mg-MOF-74 could be improved by coating with two dimensional materials h -BN. • Application of h -BN as coating material of Mg-MOF-74. • h -BN coated Mg-MOF-74 provide high surface area and enhanced CH 4 uptake capacity. • The sample Mg-MOF-74@1 wt.% h -BN exhibited the highest water stability. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) can self-assemble as cylindrical bundles in some solvents after polystyrene (PS) grafting. In these three-dimensional regular structures, the tubes are oriented and parallel arranged. Every self-assembly structure has an order head and a comparatively loose tail. In order to find out the role that solvent plays, MWCNTs were dispersed in several organic solvents before and after modification. Based on macroscopic stability of suspensions and microscopic state of nanotubes, compatibility between solvents and MWCNTs can be confirmed. According to compatibility difference between tubes and PS, five chosen solvents are divided into three groups: selective solvent, good solvent, and bad solvent. MWCNT-g-PS can self-assemble only in selective solvents. Tetrahydrofuran and benzene are well compatible with PS, but bad with MWCNTs. Driven by the solvent-philic/solvent-phobic interaction, MWCNT-g-PS self-organized regularly as bundles. Because each part of the MWCNT-g-PS is compatible well with 1,2-dichlorobenzene, gathering tendency of the modified tubes have been enervated by their good compatibility and weak amphiphilicity. Grafted or not, nanotubes reveal poor compatibility with methanol and ethanol. Strong incompatibility and limited amphiphilicity make MWCNT-g-PS agglomerate as quickly and irregularly as raw tubes. An adapted hydrophilic/lipophilic balance system is introduced to qualify compatibility and amphiphilicity of MWCNT-g-PS in each solvent. This novel model not only reveals the relationship between solvent and microscopic state of unmodified/modified tubes, but also signifies the decisive role of solvent in self-assembly behaviors of MWCNT-g-PS. [ABSTRACT FROM AUTHOR]

Abstract: Molecular structural mechanics based finite element method is applied to study the influence of the two types of Stone–Wales defects on the elastic properties of monolayer and multilayer graphene nanofilms. Models with spatial frame structures are developed to simulate the graphene crystal with Stone–Wales defects based on the linkage between the inter-atomic potential energy in molecular mechanics and the strain energy in classical structural mechanics. Several possible influencing factors, including the number and types of Stone–Wales defects, the distance between two defects and the position of defects in the graphene, are taken into account to evaluate Young''s moduli and Poisson''s ratios of armchair and zigzag monolayer graphene nanofilms. It is shown that the Stone–Wales defects have remarkable influence on the elastic properties of monolayer graphene. In addition, the size-dependent Young''s moduli and Poisson''s ratios of multilayer graphene nanofilms are also investigated when the Stone–Wales defects in surface layers are taken into consideration. [Copyright &y& Elsevier]

Abstract: This work presents six CuII, CoII, and NiII supramolecular complexes assembled from a bent dipyridyl ligand 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (3-bpo) and R-isophthalic acids (R =–CH3 for 5-methylisophthalic acid or R =–OCH3 for 5-methoxyisophthalic acid), which have been prepared using the layer-separation diffusion method and fully characterized by IR, elemental analysis, and powder X-ray diffraction (PXRD) techniques. Single-crystal X-ray diffraction indicates that these complexes show 1-D tube-like (for CuII complexes 1 and 2) or discrete cage-like dinuclear (for CoII and NiII complexes 3–6) coordination patterns. Furthermore, extended 3-D supramolecular architectures are constructed via secondary interactions between the coordination arrays, and three types of packing fashions are observed for the dinuclear species 3–6. Structural diversification for these complexes can be properly attributed to the inherent discrepancy of metal ions and the substituent effect of R-isophthalate tectons. [Copyright &y& Elsevier]

A new supramolecular compound [Zn(H2EDTA)(H2O)](Q)2(H2O)2 (1), where H4EDTA=ethylenediaminetetraacetic acid and Q=4-(carboxylate)pyridinium, has been prepared by mild hydrothermal reaction and characterized by elemental analysis, IR spectrum and thermogravimetric analysis. Single-crystal X-ray diffraction of 1 [monoclinic, space group C2/c, a=11.310(4) Å, b=9.704(4) Å, c=23.798(10) Å, β=97.401(10)°, Z=4] revealed that the ZnII ion coordinates to the chelating tetradentate ligand H2EDTA and a water molecule, taking a distorted trigonal-bipyramid geometry. The mononuclear [Zn(H2EDTA)(H2O)] subunits are linked to form two-dimensional layered architectures by the lattice water moieties through O–H⋯O hydrogen bonds, which are further extended to a three-dimensional (3D) supramolecular network by 4-(carboxylate)pyridinium guests (resulting from the ring-opening hydrolysis of 2,5-bis(4-pyridyl)-1,3,4-oxadiazole) through extensive hydrogen-bonding interactions. The 3D supramolecular framework is also stabilized by significant face-to-face π–π stacking interactions between the aromatic pyridinium systems. [Copyright &y& Elsevier]

The crystal structure of the title complex, trans-dichloridotetrakis[1-phenyl-3-(1 H-1,2,4-triazol-1-yl-κ N4)propan-1-one]copper(II) hexahydrate, [CuCl2(C11H11N3O)4]·6H2O, is isomorphous with that of the corresponding nickel and cobalt compounds. The complex has crystallographic inversion symmetry with the CuII atom on an inversion centre. Each CuII atom is six-coordinated by one N atom from each of the four 1-phenyl-3-(1 H-1,2,4-triazol-1-yl)propan-1-one ligands in the equatorial plane and by two chloride ligands in axial positions. The structure includes a centrosymmetric irregular up-up-down-down (uudd) water tetramer cluster and O-H...Cl hydrogen bonds. Intermolecular C-H...Cl hydrogen bonds exist between adjacent molecules, resulting in a three-dimensional supramolecular network. [ABSTRACT FROM AUTHOR]

C19H25N7O7, triclinic, P1 (no. 2), a = 6.969(2) Å, b = 9.300(3) Å, c = 17.214(5) Å, α = 98.231(5)°, β = 96.842(6)°, γ= 90.945(5)°, V = 1095.7 Å3, Z = 2, Rgt(F) = 0.0501, wRref(F2) = 0.1415, T = 273 K. [ABSTRACT FROM AUTHOR]

Two binuclear lanthanide complexes [Ln 2 (hfac) 6 (HL) 2 ] (Ln III = Dy( 1 ), Tb( 2 ); hfac = hexafluoroacetylacetonate, HL = (R)-2-amino-2-phenylethanol) have been successfully obtained by using amino alcoholate ligand. In two complexes, the Ln(III) ions are bridged by two alkoxido groups from HL ligands, resulting in binuclear complexes. The variable-temperature magnetic susceptibility studies indicate that there exists ferromagnetic interaction between two Ln(III) ions. Frequency dependent out-of-phase signals are observed for complex 1 , suggesting SMM type behavior. Complexes 1 and 2 display intensely characteristic luminescent properties. [ABSTRACT FROM AUTHOR]

In this work a flexible multi-dentate 1-(4-aminobenzyl)-1,2,4-triazole (abtz) ligand has been employed, two novel triazole-Cu(II) coordination polymers {[Cu(abtz) 2 (Br) 2 ]·(H 2 O) 2 } n ( 1 ) and {[Cu(abtz) 2 ]·(SiF 6 )·(H 2 O) 2 } n ( 2 ) have been isolated under solvo-thermal conditions. 1 is a 2D neutral Cu II coordination polymer while 2 is 2D cation micro-porous Cu II coordination polymer with the channel dimensionalities of 11.852(1) Å × 11.852(1) Å (metal-metal distances). Variable-temperature magnetic susceptibility data of 1 and 2 have been recorded in the 2–300 K temperature range indicating weak anti-ferromagnetic interactions. Further absorption properties of anion pollutants for 2 also have been investigated. 2 presents the novel example of cationic triazole-copper(II) coordination framework for effectively capturing anion pollutants Cr 2 O 7 2− in the water solutions and selectively capturing Congo Red in the methanol solutions. [ABSTRACT FROM AUTHOR]

C38H34Ni2Cl2N4O12, monoclinic, C2/c (no. 15), a = 17.867(3) Å, b = 9.170(6) Å, c = 24.651(5) Å, β = 110.837(2)°, Z = 4, V = 3775(3) Å3, Rgt(F) = 0.0323, wRref(F2) = 0.1078, T = 293(2) K. [ABSTRACT FROM AUTHOR]

Abstract: A series of 10,10-dioctyl-3,6-dihydrofluoreno[2,3-d:6,7-d′]diimidazole derivatives were conveniently synthesized by condensation of the key intermediate 2,3,6,7-tetraamino-9,9-dioctylfluorene (TADOF) with aldehydes under very mild conditions. All of the target compounds were characterized using 1H NMR, 13C NMR, and elemental analysis. The crystal structure of 3,6-dibenzyl-10,10-dioctyl-2,7-diphenyl-6,10-dihydro-3H-fluoreno[2,3-d:6,7-d′]diimidazole was determined as triclinic, space group P-1 type, using single X-ray crystallography. For seventeen samples, UV–visible absorption maximum wavelength (λ max), fluorescence excitation wavelength (λ ex), fluorescence emission wavelength (λ em) and fluorescence quantum yield (φ FL) were measured in dilute dichloromethane solution and in the solid state. These compounds possess a medium strong blue fluorescence-emitting ability with φ FL values in the region of 0.30–0.89 and structure-optical behavior characteristics were discussed. [Copyright &y& Elsevier]

Abstract: The interaction of LiN(SiMe3)CH2Ph with one equivalent of benzenitrile gave the N-silyl-N′-benzyl-benzamidinato-lithium compound [{Me3SiNC(Ph)N(CH2Ph)}Li(Et2O)]2 (1). The derivative zirconium and hafnium compounds were produced by the treatment of 1 with ZrCl4 or HfCl4 in tetrahydrofuran or diethyl ether at ambient temperature, respectively, with the general formula [Me3SiNC(Ph)N(CH2Ph)]3MCl (M=Zr (2), Hf (3)). Compounds 1, 2 and 3 were also characterized by X-ray single crystal diffraction and NMR analysis. [Copyright &y& Elsevier]

The reaction of 2,5-bis(2-pyridyl)-1,3,4-oxadiazole (L1) with Cu(OAc)2·H2O salt in a CH3OH/CH3CN medium produces a new monometallic copper(II) complex 1 [Cu(L4)(OAc)(H2O)](H2O)2(CH3CN), where HL4=N-(α-hydroxyl-2-pyridyl)-N′-(α-methoxy-2-pyridyl)ketazine (C13H12N4O2), which was characterized by IR, UV–vis and elemental analysis, and established by X-ray diffraction technique. The results reveal that metal-assisted alcoholysis of L1 leads to the open of the central oxadiazole ring to give a new ligand HL4 during this course. In the crystal structure of complex 1, L4 acts as a tridentate chelating anionic ligand to coordinate to the CuII center, which lies in a square-pyramid coordination environment. Additionally, hydrogen-bonding interactions also play an important role in the self-assembly process. The mechanism of the metal-assisted alcoholysis of L1 in formation of complex 1 was discussed in detail and the spectral properties of 1 were also investigated. [Copyright &y& Elsevier]

The cross-correlation technology is applied to decrease the noise figure of microwave photonic link(MPL) for the first time in this paper. Firstly, both effects of the intensity of the laser and the bias voltage of the EOM on the noise figure of MPL are analyzed and optimized. Then, a cascaded low-noise amplifier is added in front of MPL for lower noise figure. Finally, the double laser - double detector structure based on cross-correlation technology is used to offset different kinds of uncorrelated noise in the link and experiments show that the noise figure is further reduced by 3 dB. [ABSTRACT FROM AUTHOR]

Sodium praseodymium orthophosphate Na 3 Pr(PO 4 ) 2 was prepared using high temperature molten salt method and structurally characterized by single-crystal X-ray diffraction (SC-XRD) analysis. Its structure can be modeled as a four-dimensional (4D) commensurately modulated structure with orthorhombic superspace group Pca 2 1 (0 1/3 0)000 or as a conventional 3D superstructure description. The structure contains PrO 8 , NaO 6 , NaO 7 and PO 4 polyhedra, which are in six types of linear array along the a -axis. Furthermore, the excitation and emission spectra, decay time and Commission International de l’Éclairage (CIE) chromaticity index of Na 3 Pr(PO 4 ) 2 were studied. Under blue light excitation (468 nm), the powdered Na 3 Pr(PO 4 ) 2 calcined at 1200 °C shows the strongest red emission at around 610 nm, which originates from the 3 P 0 → 3 H 6 and 1 D 2 → 3 H 4 transformations of Pr 3+ ion. [ABSTRACT FROM AUTHOR]

An unexpected polyhydroxyl-bridged tetranuclear ZnII complex and a benzoquinone compound derived from metal-ion promoted reactivity of Schiff base ligands were synthesized and characterized. The reaction of zinc(II) acetate dihydrate with oxime-type Schiff base ligand HL1 [HL1 = 1-(3-((3,5-dibromosalicylaldehyde)amino)phenyl) ethan-1-one O-benzyl oxime] in methanol, acetone and acetonitrile resulted in the chemoselective cleavage of the C=N bond of the Schiff base HL1 and then the further addition of acetone to two salicylaldehyde molecules derived from cleavage of the C=N bond in situ α,α double aldol reaction promoted by ZnII ions. The newly formed ligands H4L2 coordinate to four ZnII ions forming a defect-dicubane core structure [ZnII 4(H2L2)2(μ3-OCH3)2(μ-OCH3)2(CH3OH)2] (1) bridged exclusively by oxygen-based ligands. The similar ligand HL3 [HL3 = 1-(3- ((3,5-dichlorosalicylaldehyde)amino)phenyl)ethan-1-one O-benzyl oxime)] was employed to react with CdII acetate dihydrate under the same reaction conditions. No aldol addition occurred but a unexpected benzoquinone compound 2,5-bis(((3-(1-((benzyloxy)imino)ethyl) phenyl)imino)methyl)-1,4-benzoquinone (2) formed. The results provided interesting insights into one-pot routes involving in situ reactions act as a strategy for obtaining a variety of polymeric/polynuclear complexes which are inconvenient to obtain from directly presynthesizing the ligands. [ABSTRACT FROM AUTHOR]

Based on the bis-triazole ligand 2, 6-bis(1, 2,4-triazole-4-yl)pyridine (L), the triazole-iron(II) complexes [Fe(L)2(dca)2(H2O)2] ·2H2O ( 1) (Nadca = sodium dicyanamide), {[Fe(μ2-L)2(H2O)2]Cl2} n ( 2), and {[Fe(μ2-L)2(H2O)2](ClO4)2 ·L ·H2O} n ( 3) were isolated by solvent diffusion methods. When iron(II) salts and Nadca were used, compound 1 was isolated, which contains mononuclear Fe(L)2(dca)2(H2O)2 units. When FeCl2 or FeClO4 were used, one-dimensional (1D) cation iron(II) chains ( 2) and two-dimensional (2D) cation iron(II) networks ( 3) were isolated indicating anion directing structural diversity. Moreover, variable-temperature magnetic susceptibility data of 1- 3 were recorded in the temperature range 2-300 K. The magnetic curve of complex 2 was fitted by using the classical spin Heisenberg chain model indicating anti-ferromagnetic interactions ( J = -5.31 cm-1). Obviously complexes 1- 3 show no detectable thermal spin crossover behaviors, the lack of spin-crossover behavior may be correlated with FeN4O2 coordination spheres in 1- 3. [ABSTRACT FROM AUTHOR]

1,2,5-thiadiazole-3,4-dicarboxylic acid (H tdzdc) ligand has been used to construct three coordination compounds [Mg(tdzdc)(HO)]( 1), [Ca(tdzdc)(HO)]( 2) and [Sr(tdzdc)(HO)]( 3) by the solvothermal reaction. Single-crystal structure analyses reveal a mononuclear coordination structure for compound 1 and two dimensional coordination structure both for compound 2 and 3. Furthermore, all of these three compounds comprise any amount of hydrogen bond interactions, which extends their crystal structure into three dimensional (3D) frameworks. Different crystal structure of compounds 1- 3 reveals diversified coordination modes of H tdzdc ligand toward alkaline earth metal ions, depending mainly on the radius and the electron shell number of metal ions used. Graphical Abstract: Based on 1,2,5-thiadiazole-3,4-dicarboxylic acid (H tdzdc) ligand, three new alkaline earth metal compound were synthesized with different structure.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Highlights: [•] LiNi1/3Co1/3Mn1/3O2 is designed into new core-shelled structure. [•] Core-shelled layered oxides present better cycleability. [•] The significantly improved safety property is observed for core-shelled samples. [Copyright &y& Elsevier]

Cobalt(II) and copper(II) complexes with deprotonated N-[2'-(4-methyl)pyrimidinyl]-2-nitrobenzenesulfonylurea were synthesized and their structures were characterized by IR spectrum, elemental analysis and X-ray diffraction. The deprotonated sulfonylurea is a bidentate ligand to Co(II) or Cu(II) in octahedral geometry. In the packing diagrams of the complexes, C-H ··· O hydrogen bonds are observed. The UV and fluorescence spectra of the complexes are described, and the thermogravimetric analyses of the complexes were performed. [ABSTRACT FROM AUTHOR]

Abstract: Assemblies of an angular dipyridyl ligand 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (4-bpo) with a series of metal perchlorate afford five new supramolecular complexes with the general formula of [M(4-bpo)2(H2O)4]·(4-bpo)2 ·(anion)·(solvent), in which M=MnII for 1, FeII for 2, CoII for 3, ZnII for 4, and FeIII for 5. Although similar molecular structures and compositions are found for these mononuclear complexes, they display two types of supramolecular lattices. Complexes 1, 4 and 5 similarly crystallize in space group P2/n or P2/c. The complex cations, free 4-bpo and lattice water are linked to generate 2D layered frameworks with the aid of hydrogen bonding, and the counter anions are located within and between (also methanol in 5) these 2D arrays. However, complexes 2 and 3 are isostructural in space group . Two types of alternate 2D layers consisting of complex cations and free 4-bpo components, respectively, are observed with the anions and lattice water locating between them. These motifs are interlinked by complicated hydrogen-bonding to form a 3D intercalated network. Moreover, when Co(NO3)2 is used instead of Co(ClO4)2 in the assembly of 3, a 1D polymeric chain complex {[Co(4-bpo)(H2O)2(NO3)2](H2O)3} n (6) is generated. These results indicate that the choice of metal ion and anion exerts a significant influence on governing the target complexes. A comparison of the structural features for all metal perchlorate complexes with 4-bpo is also briefly discussed. [Copyright &y& Elsevier]

The interaction of PdCl2(PhCN)2 with 1,2-[PhP(H)CH2CH2CH2P(Ph)CH2]2C6H4, generated in situ from the reduction of the corresponding phosphine oxide with LiAlH4 in the presence of Me3SiCl, gave a complex mixture, from which a di- and a tetra-nuclear palladium complex 1 and 2 whose solid state structures were ascertained by X-ray crystallography, were isolated. A novel Pd(0)–Pd(IV)–Pd(IV)–Pd(0) mixed-valence structure was observed in complex 2. [Copyright &y& Elsevier]

• The Schiff base binuclear Zn(II) complex, [Zn 2 (L) 2 ∙(H 2 O) 2 ]∙2DMF (1) and its coordination polymer, [Zn 2 (L) 2 ∙(4,4′-bpy) 2 ] n (2) by introducing auxiliary ligand 4,4′-bpy. • The fluorescence spectrum showed the complex 2 containing 4,4′-bpy was substantially quenching of the fluorescence as compared with the complex 1. • The LUMO and HOMO orbits of the complex 2 were occupied by the 4,4′-bpy, which is different from complex 1 , resulting in 1 and 2 had different spectral properties. The Schiff base binuclear Zn(II) complexes, [Zn 2 (L) 2 ∙(H 2 O) 2 ]∙2DMF (1) and its coordination polymer [Zn 2 (L) 2 ∙(4,4′-bpy) 2 ] n (2) (H 2 L = 3-[(5-chloro-2-hydroxy-benzylidene)-amino]-4-hydroxy-chromen-2-one, 4,4′-bpy = 4,4′-bipyridine), were synthesized under the same experimental condition without or with the auxiliary ligand 4,4′-bpy, respectively. The structural analysis revealed that complexes 1 and 2 have different crystal structures. The complex 1 was a centrosymmetric binuclear structure. It is noteworthy that the linker 4,4′-bpy was introduced during the synthesis of complex 2 , so that two water molecules in complex 1 were replaced by two 4,4′-bpy linkers to form one-dimensional (1D) chain-like coordination polymer. The central Zn(II) ions in complex 1 were penta-coordinated distorted square pyramid geometry with τ = 0.42. However, the Zn(II) ions of complex 2 were hexa-coordinated distorted octahedral geometry. The fluorescence spectrum showed the complex 2 containing 4,4′-bpy was substantially quenching of the fluorescence as compared with the complex 1. In addition, it could be seen from the DFT calculation the energy gaps of the complexes 1 and 2 were both reduced compared to the ligand H 2 L. However, the LUMO and HOMO orbits of the complex 2 were occupied by the 4,4′-bpy, which is different from complex 1 , resulting in 1 and 2 had different spectral properties. [ABSTRACT FROM AUTHOR]

Three layered compounds CsLiCoS 2 , CsAgCoS 2 and CsLiFeS 2 have been synthesized by conventional solid-state reaction method. All of three compounds exhibit semiconducting behavior in electrical transport with small thermal activation energy gap. The crystal structure of CsLiCoS 2 is isostructural to ThCr 2 Si 2 -type CsCo 2 S 2 with random mixture of Li+ and Co2+. The latter two compounds exhibit √2 ​× ​√2 ​× ​1 superstructure of ThCr 2 Si 2 -type because the monovalent Ag+/Li+ and divalent Co2+/Fe2+ independently occupy inequivalent sites in [AMS 2 ]- layer. Through comprehensive investigation of the crystallographic lattice in CsAMS 2 , a phase boundary between disorder and ordered phases may be identified, which highlights the importance of the atomic size and lattice mismatch in determining the crystal structure. Image 1 • Three layered sulfides CsAMS 2 (A ​= ​Li, Ag; M ​= ​Co, Fe) are synthesized by solid state reaction method. • Introducing monovalent Li+/Ag+ could significantly change the structure and property of Co-based sulfides. • A phase boundary between random and ordered occupation in the [AMS 2 ]- layers is determined by the atomic size difference. [ABSTRACT FROM AUTHOR]

Reaction of dilithium derivatives of N,N’-(dimethylsilanediyl)diamines, Me2Si[N(Li)R]2 with benzonitrile followed by treatment with Me2SiCl2 afforded 1,3-bis[1-(N-R-imino)-1-phenylmethyl]-1,3,2,4-diazadisiletidines, the neutral four-membered bissilylene-linked bisamidines, whose structure was established by X-ray diffraction. [Copyright &y& Elsevier]