Unexpected transformation of a diamagnetic Mo3(μ3-S)(μ-S)3 to a paramagnetic Mo3(μ3-S)2(μ-S)3 cluster core by reaction of [Mo3S4(dppe)3Br3]PF6 with tBuSNa

Paramagnetic Rhenium Iodide Cluster with N-Heterocyclic Carbene

triangulo-Trirhenium nonaiodide Re₃I₉ reacts with 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes) to produce the novel 13-electron paramagnetic cluster Re₃I₈(IMes)₂, which was characterized by means of X-ray diffraction analysis, ESR spectroscopy, magnetometry, and quantum chemistry.

A Sterically Hindered Derivative of 2,1,3-Benzotelluradiazole: A Way to the First Structurally Characterised Monomeric Tellurium-Nitrogen Radical Anion

Interaction of the tetradentate redox-active 6,6'-[1,2-phenylenebis(azanediyl)]bis(2,4-di-tert-butylphenol) (H₄ L) with TeCl₄ leads to neutral diamagnetic compound TeL (1) in high yield. The molecule of 1 has a nearly planar TeN₂ O₂ fragment, which suggests the formulation of 1 as Te^II L^2- , in agreement with the results of DFT calculations and QTAIM and NBO analyses. Reduction of 1 with one equivalent of [CoCp₂ ] leads to quantitative formation of the paramagnetic salt [CoCp₂ ]⁺ [1]^.- , which was characterised by single-crystal XRD. The solution EPR spectrum of [CoCp₂ ]⁺ [1]^.- at room temperature features a quintet due to splitting on two equivalent ¹⁴ N nuclei. Below 150 K it turns into a broad singlet line with two weak satellites due to the splitting on the ¹²⁵ Te nucleus. Two-component relativistic DFT calculations perfectly reproduce the a(¹⁴ N) HFI constants and A_∥ (¹²⁵ Te) value responsible for the low-temperature satellite splitting. Calculations predict that the additional electron in 1^.- is localised mainly on L, while the spin density is delocalised over the whole molecule with significant localisation on the Te atom (≥30 %). All these data suggest that 1^.- can be regarded as the first example of a structurally characterised monomeric tellurium-nitrogen radical anion.

[{(PhSn)3SnS6}{(MCp)3S4}] (M = W, Mo): Minimal Molecular Models of the Covalent Attachment of Metal Chalcogenide Clusters on Doped Transition Metal Dichalcogenide Layers

With the aim to mimic the yet unknown covalent deposition of metal chalcogenide clusters on transition metal dichalcogenide (TMDC) MoS₂ or WS₂ layers, and thereby explore the interaction between the two systems and potential consequences on physical properties of the TMDC material, we synthesized heterobimetallic model systems. The heterocubane-type cluster [(SnCl₃)(WCp)₃S₄] (1), the organotin-sulfidomolybdate cluster [{(PhSn)₃SnS₆}{(MoCp)₃S₄}] (2), and the corresponding tungstate [(PhSn)₃SnS₆{(WCp)₃S₄}] (3) were obtained in ligand exchange reactions from [(PhSn)₄S₆] and [M(CO)₃CpCl]. Indeed, the {M₃S₄} cages in 1-3 resemble a section of the respective TMDC monolayers, altogether representing minimal molecular model systems for the adsorption of organotin sulfide clusters on MoS₂ or WS₂. The interaction between the {(MCp)₃S₄} and {(PhSn)₃SnS₆} subunits is characterized by multicenter bonding, rendering the respective Sn atom as Sn(II), hence driving the clusters into a mixed-valence Sn(IV)/Sn(II) situation, and the M atoms as M(IV) upon an in situ redox process. The attachment is thus weaker than via regular covalent M-S bonds, but definitely stronger than via van der Waals interactions that have been characteristic for all known interactions of clusters on TMDC surfaces so far. Computational analyses of an extended model mimicking the electronic situation in the cluster prove the analogy to a covalent attachment on TMDCs.

The first heterocubane cluster with a [W3GaS4] core

The paramagnetic cuboidal clusters [Mo₃(GaCl)(μ₃-S)₄(dppe)₃Cl₃] and [W₃(GaBr)_0.81(μ₃-S)₄(dppe)₃Br₃] were synthesized by treatment of the corresponding triangular clusters [M₃S₄(dppe)₃X₃]X with [Ga(η⁵-C₅Me₅)]₆.

Tris(tetra-butyl-ammonium) hexa-kis-(tert-butane-thiol-ato-κS)hepta-μ(3)-chlorido-μ(3)-sulfido-hexa-molybdate dihydrate

The octa­hedral cluster core of the anion in the structure of the title compound, (C₁₆H₃₆N)₃[Mo₆(C₄H₉S)₆(μ₃-Cl)₇(μ₃-S)]·2H₂O, has -3 site symmetry. Two μ₃-Cl atoms fully occupy positions in the cluster core, while the remaining six positions are statistically occupied by Cl and S atoms in a 1:5 ratio. The fully occupied Cl-atom positions are located on sites with 3 symmetry, and the N atom of tetra­butyl­ammonium cation is located on a site with 2 symmetry. The structure contains also two disordered solvent water mol­ecules, one of which is located on a threefold rotation axis and the other in a general position, both with an occupancy of 0.25. The water mol­ecules are localized in cavities formed by the tetra­butyl­ammonium cations and the tert-butane­thiol­ate groups. The metal clusters are stacked in a cubic close packing arrangement along [001].