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This study investigates the influence of chromium and molybdenum content (Cr: 20–35 wt%; Mo: 5 and 10 wt%) in a cobalt–chromium–molybdenum alloy system on the phases present in the microstructure, the nanomechanical, and electrochemical behavior of the alloys. A linear increase in the hardness is found in relation to the increasing chromium content for both 5 and 10 wt% Mo contents, whereas reduced modulus demonstrates an inflection at 30 wt% Cr, which is influenced by the molybdenum content. The open‐circuit potential, polarization resistivity, and linear sweep voltammetry disclose that passivity of Co–Cr–Mo alloys improves in line with increasing Cr until 30 wt%, with any further increase causing a depreciation in the corrosion properties. X‐Ray diffraction and optical metallographic analysis confirm that as the chromium content transitions through the 25–30 wt% range, the sigma (σ) phase begins to develop within the combined matrix of hexagonal close pack martensite (ε) and face‐centered cubic austenite (γ) phase. [ABSTRACT FROM AUTHOR]

The hybridized lanthanide‐containing molybdenum blue (Ln‐MB) wheel Na4[Mo2O2(OH)4(C6H4NO2)2]2[Mo120Ce6O366H12(OH)2(H2O)76]∼200H2O ({Mo2(C6H4NO2)2}2{Mo120Ce6}) was assembled in an aqueous one‐pot synthesis. The Ln‐MB was hybridized with 2‐picolinic acid through the generation of the organometallic counter‐ion [Mo2O2(OH)4(C6H4NO2)2]2+. Control experiments demonstrated that the position of the carboxylic acid group (2‐position to the N atom) in the hybridization component is critical in yielding single crystals of Ln‐MB. In addition to single‐crystal X‐ray diffraction (XRD) analysis, which revealed a 'Japanese rice‐ball'‐shaped Ln‐MB as the anion, elemental analyses, IR spectroscopy, and thermogravimetric analysis (TGA) were performed to confirm its structure and composition. Bond‐valence‐sum calculations (BVS) revealed that {Mo2(C6H4NO2)2}2{Mo120Ce6} is composed of a 24‐electron reduced anionic ring, which was confirmed by Vis–NIR spectroscopy. [ABSTRACT FROM AUTHOR]

The synthesis and structural determination of two isomers of the molybdenum(II) complex (η2‐but‐2‐yne)carbonylbis[2‐(4,4‐dimethyl‐4,5‐dihydro‐1,3‐oxazol‐2‐yl)benzenethiolato‐κ2N,S]molybdenum(II), [Mo(C11H12NOS)2(C4H6)(CO)] or Mo(CO)(C2Me2)(S‐Phoz)2, are presented. The N,N‐cis–S,S‐trans isomer 1 shows quite different bond lengths to the metal atom [Mo—N = 2.4715 (10) versus 2.3404 (11) Å; Mo—S = 2.4673 (3) versus 2.3665 (3) Å]. In the N,N‐trans–S,S‐cis isomer 2, which is isotypic with the corresponding W complex, the Mo—N bond lengths [2.236 (2) and 2.203 (2) Å], as well as the Mo—S bond lengths [2.5254 (8) and 2.5297 (8) Å], are almost the same. [ABSTRACT FROM AUTHOR]

The Schiff‐base condensation of salicylaldehyde and 4‐aminobutanehydrazide hydrochloride leads to the hydrazone‐based ligand H2salhyab containing an amino side chain. The reaction of H2salhyab ⋅ HCl with bis(acetylacetonato)dioxidomolybdenum leads to the formation of [MoO2(salhycab)(MeOH)] (H2salhycab=2‐((pyrrolidine‐2‐ylidenehydrazineylidene)methyl)phenol), whereby the amino side chain reacted with the hydrazide carbonyl group to form a cyclic amidine with a pyrrolidine ring leading a new type of tridentate hydrazone ligand with [NNO] donor set. X‐ray crystallography revealed the additional coordination of a methanol molecule at the molybdenum(VI) center which leads to the formation of hydrogen‐bonded dimers of the neutral complex in the crystal structure. The complex [MoO2(salhycab)(MeOH)] was found to be an efficient catalyst for the peroxidic oxidation of phenyl methyl sulfide. [ABSTRACT FROM AUTHOR]

Molybdenum and tungsten iodide clusters with the [M6I8] cluster core show versatile photophysical properties that strongly depend on the nature of six apical ligands (L) in [M6I8L6]2–. In course of our syntheses we report a new efficient preparation of Cs2[Mo6I14] as precursor. Target compounds (nBu4N)2[M6I8(NCO)6] with M = Mo, W with cyanate ligands were synthesized and structurally characterized to study their photophysical properties. (nBu4N)2[M6I8(NCO)6] compounds appear as deep red (Mo) and light yellow (W) crystal powders showing strong phosphorescence. Compared to other cluster compounds of this type there is no significant concentration quenching obtained by the presence of molecular oxygen. [ABSTRACT FROM AUTHOR]

Single crystals of Tl4.86Fe0.82Hf1.18(MoO4)6 [a = b = 10.5550 (3), c = 37.7824 (9) Å, γ = 120°] are obtained by the self‐flux method in the Tl2MoO4–Fe2(MoO4)3–Hf(MoO4)2 system. On the differential scanning calorimetry curve in the temperature range 320–350 K and at T ∼ 690 K, endothermic peaks are observed. The second harmonic generation test shows an excess of the signal of the quartz standard by almost three times at room temperature. In the range 320–340 K its intensity decreases by almost three times and at T ∼ 700 K it drops to zero. In the same interval, the temperature dependences of the unit‐cell parameters and volume show stepwise changes. According to the X‐ray diffraction data, the crystal structure consists of nonpolar and polar domains with different local symmetries. The structure is a three‐dimensional framework consisting of alternating (Hf,Fe)O6 octahedra connected by MoO4 tetrahedra. Hf and Fe atoms occupy mixed Hf/Fe positions with different probabilities: 0.77:0.23, 0.50:0.50 and 0.32:0.68. Tl cations are located inside the framework in zigzag channels extended along the a and b axes. The thallium arrangement is disordered, i.e. it involves additional positions and vacancies. The complex crystal structure has been solved using the nonstandard space group R1, taking into account the local symmetry R3c for the Mo atoms and mixed Hf/Fe positions mainly occupied by Hf atoms. The possible paths of ion transport are analyzed. The energy required to overcome the potential barrier between sites of Tl cations to migrate, which corresponds to the activation energy of conductivity, is estimated. The ion current is shown to be most probable in the ab plane. [ABSTRACT FROM AUTHOR]

The reactions of the fluoride‐ion donor, XeF6, with the fluoride‐ion acceptors, M′OF4 (M′=Cr, Mo, W), yield [XeF5]+ and [Xe2F11]+ salts of [M′OF5]− and [M2O2F9]− (M=Mo, W). Xenon hexafluoride and MOF4 react in anhydrous hydrogen fluoride (aHF) to give equilibrium mixtures of [Xe2F11]+, [XeF5]+, [(HF)nF]−, [MOF5]−, and [M2O2F9]− from which the title salts were crystallized. The [XeF5][CrOF5] and [Xe2F11][CrOF5] salts could not be formed from mixtures of CrOF4 and XeF6 in aHF at low temperature (LT) owing to the low fluoride‐ion affinity of CrOF4, but yielded [XeF5][HF2]⋅CrOF4 instead. In contrast, MoOF4 and WOF4 are sufficiently Lewis acidic to abstract F− ion from [(HF)nF]− in aHF to give the [MOF5]− and [M2O2F9]− salts of [XeF5]+ and [Xe2F11]+. To circumvent [(HF)nF]− formation, [Xe2F11][CrOF5] was synthesized at LT in CF2ClCF2Cl solvent. The salts were characterized by LT Raman spectroscopy and LT single‐crystal X‐ray diffraction, which provided the first X‐ray crystal structure of the [CrOF5]− anion and high‐precision geometric parameters for [MOF5]− and [M2O2F9]−. Hydrolysis of [Xe2F11][WOF5] by water contaminant in HF solvent yielded [XeF5][WOF5]⋅XeOF4. Quantum‐chemical calculations were carried out for M′OF4, [M′OF5]−, [M′2O2F9]−, {[Xe2F11][CrOF5]}2, [Xe2F11][MOF5], and {[XeF5][M2O2F9]}2 to obtain their gas‐phase geometries and vibrational frequencies to aid in their vibrational mode assignments and to assess chemical bonding. [ABSTRACT FROM AUTHOR]

Treatment of molybdenum(II) acetate with thioether functionalized silylamides R2Si(NLi‐C6H4–2‐SR')2 leads to the formation of dinuclear MoII complexes [Mo2{R2Si(NC6H4‐2‐SR')2}2]. According to X‐ray crystal structure analyses the complexes [Mo2{Me2Si(NC6H4‐2‐SMe)2}2] and [Mo2{Ph2Si(NC6H4‐2‐SPh)2}2] comprise a Mo2‐unit which is coordinated by two μ‐κ‐N,N' silylamide ligands. The coordination sphere around the molybdenum atoms consists of two amide nitrogen atoms and two thioether sulfur atoms in a distorted square‐planar arrangement. The Mo‐Mo distances are 211.0(1) and 211.7(1) pm, resp. In the complex [Mo2{Ph2Si(NC6H4‐2‐SMe)2}2] the silyl amide units act as tetradentate κ‐N,N',S,S'chelating ligands and the Mo‐Mo distance is 218.6(1) pm. [ABSTRACT FROM AUTHOR]

Many successful battery electrodes are based on 2D‐layered materials. Aluminum‐ion batteries are studied using molybdenum dichalcogenides: MoS2, MoSe2, and MoSSe as active cathode materials. The batteries show clear discharge voltage plateaus in the ranges 1.6–1.4 V for MoS2 and MoSe2, and 0.6–0.5 V for MoSSe. MoS2 and MoSe2 have similar crystal structures; interestingly, it is found that MoSe2 performed better than MoS2. MoSSe exhibits a higher specific capacity over MoS2 and MoSe2, but the energy density is lower than MoSe2 at a current rate of 40 mA g−1. MoSe2 cells record a discharge capacity of ≈110 mAh g−1 with an average potential in the range of 2.0–1.8 V and 1.5–0.8 V during discharge. The cells are stable at 100 mA g−1 for over 200 cycles with 90% coulombic efficiency. [ABSTRACT FROM AUTHOR]

The hexafluoridomolybdates(V), A[MoF6] (A = Li – Cs), were synthesized by reacting molybdenum pentafluoride (MoF5) with the alkali metal fluorides in anhydrous hydrogen fluoride (aHF) solution. Single crystals of A[MoF6] (A = Li, Na, Rb, Cs) were grown from solution and analyzed by single‐crystal X‐ray diffraction. The vibrational spectrum of each salt is reported in detail and compared to previously reported spectra. During analysis of the cubic modification of Na[MoF6] it was noticed that a phase transition occurs around 228 K. Some details regarding this phase transition are discussed. Attempts to determine the structure of the low‐temperature phase of Na[MoF6] lead to the observation of the Na[MoF6]·2HF solvate. Additionally, in an attempt to synthesize Na[MoF7] by the oxidation of Na[MoF6] in chlorine trifluoride (ClF3), a tetragonal modification of Na[MoF6] was observed. The crystal structures of the Na[MoF6]·2HF solvate and tetragonal modification of Na[MoF6] are also discussed in detail. [ABSTRACT FROM AUTHOR]

Lamellar molybdenum disulfide (MoS2) has attracted a wide range of research interests in recent years because of its two‐dimensional layered structure, ultrathin thickness, large interlayer distance, adjustable band gap, and capability to form different crystal structures. These special characteristics and high anisotropy have made MoS2 widely applicable in energy storage and harvesting. In this Minireview, a systematic and comprehensive introduction to MoS2, as well as its composites, is presented. It is aimed to summarize the various synthetic methods of MoS2‐based composites and their application in energy‐storage devices (lithium‐ion batteries, sodium‐ion batteries, lithium–sulfur batteries, and supercapacitors) in detail. Based on recent studies, this Minireview provides important and comprehensive guidelines for further study and development efforts in the MoS2 in energy‐storage field. [ABSTRACT FROM AUTHOR]

The photoinduced properties of the octacoordinated complex K4MoIV(CN)8⋅2 H2O were studied by theoretical calculations, crystallography, and optical and magnetic measurements. The crystal structure recorded at 10 K after blue light irradiation reveals an heptacoordinated Mo(CN)7 species originating from the light‐induced cleavage of one Mo−CN bond, concomitant with the photoinduced formation of a paramagnetic signal. When this complex is heated to 70 K, it returns to its original diamagnetic ground state, demonstrating full reversibility. The photomagnetic properties show a partial conversion into a triplet state possessing significant magnetic anisotropy, which is in agreement with theoretical studies. Inspired by these results, we isolated the new compound [K(crypt‐222)]3[MoIV(CN)7]⋅3 CH3CN using a photochemical pathway, confirming that photodissociation leads to a stable heptacyanomolybdate(IV) species in solution. [ABSTRACT FROM AUTHOR]

Metal oxide nanoparticles are potentially attractive tools for biomedical applications such as bioimaging and drug delivery. This urges experimental studies of their surface interaction with biomolecules, in the first hand, amino acids and proteins. Especially intriguing is the effect of not only shape and size but of chemical nature of the particles on the nature of bonds emerging between them and biomolecules. In present study we isolated, structurally characterized and compared complexes with model molecules glycylglycine and arginine of spherically shaped Keggin POMs [PM12O40]3–, M = Mo, W as models for individual nanoparticles ca. 1 nm in size. Surprisingly, structures of the chemically analogous Mo‐ and W‐compounds were not isomorphous, and in case of arginine cations even differed in compositions. The structures of Mo‐derivatives are dominated by charge interactions, while for the W‐ones, the hydrogen bonding, leading to possible configuration changes in biomolecules, is of prime importance. Keggin POMs appear to be unstable to hydrolysis on strong dilution according to 1H and 31P NMR and electrospray ionization MS data, but are appreciably stabilized, when in complex with a peptide or an amino acid. [ABSTRACT FROM AUTHOR]

A determination of the detailed crystal structure of an Mo‐substituted lanthanum tungstate series, La6−xW1−yMoyO12−δ (0 ≤ y ≤ 0.2, δ is the oxygen deficiency), is presented. Material of composition La5.4W0.8Mo0.2O12−δ (y = 0.2) produced by the citrate‐complexation route based on the Pechini method was investigated by high‐resolution X‐ray diffraction and neutron diffraction in the temperature range 10 ≤ T ≤ 298 K. The results are compared with a non‐substituted material La5.4WO12−δ. A structural model established earlier for lanthanum tungstates and Re‐substituted lanthanum tungstates is confirmed, according to which the Wyckoff site shared by La and W is split with half site occupancies (space group, 48h site) and also accommodates Mo atoms. Substitution of W by up to 20 mol% Mo does not change the face‐centred cubic lattice: Mo atoms substitute W statistically on both 4a and 48h Wyckoff sites of the crystal structure, which is described by the space group. These results were obtained from the combination of the average neutron‐scattering length and average X‐ray scattering power procedures with electron‐probe micro‐analysis. The temperature dependence of bond lengths in dry and wet (D2O) conditions shows that vacant oxygen sites are located on the 32f Wyckoff sites also in Mo‐substituted lanthanum tungstates, and that the bond lengths between La on 4b and O on 32f increase with increasing pO2 and pD2O, reflecting the filling of oxygen vacancies and the increase in coordination of La on 4b. [ABSTRACT FROM AUTHOR]

Previous studies performed on samples of MoOF4 dissolved in anhydrous hydrogen fluoride (aHF) solutions have indicated the presence of the [Mo2O2F9]– anion. Building upon this earlier work, MoOF4, and MF (M = Li–Cs) were dissolved in aHF solutions to produce M[Mo2O2F9] (M = Li–Cs) salts. Structural analysis of the obtained compounds was performed using single‐crystal X‐ray diffraction. This study provides the first single crystal structures for the [MoVI2O2F9]– anion. Additionally, IR and Raman spectroscopy were used to characterize each salt. These spectra were compared to calculated ones for the solid‐state structure of each salt using the DFT‐PBE0 density functional method. The calculated spectra were used to give band assignments in the experimentally obtained spectra. [ABSTRACT FROM AUTHOR]

Pure anhydrous Cu(CH3COO)2 was obtained both, by thermal dehydration of Cu(CH3COO)2·H2O and by drying a commercially purchased mixture of Cu(CH3COO)2·H2O and Cu(CH3COO)2 in a nitrogen atmosphere using P2O5 as drying agent. The crystal structure was solved ab initio from synchrotron X‐ray powder diffraction (XRPD) data at 150 °C and from laboratory XRPD data at ambient conditions and found to be isotypic to anhydrous chromium(II), molybdenum(II) and rhodium(II) acetate. Cu(CH3COO)2 crystallizes in space group P1 (no. 2) with lattice parameters of a = 5.1486(3) Å, b = 7.5856(6) Å, c = 8.2832(6) Å, α = 77.984(4)°, β = 75.911(8)°, γ = 84.256(6)° at ambient conditions. Cu2(CH3COO)4 paddle wheels with short (2.6 Å) Cu–Cu distances form chains in a direction, which is the main motif in the crystal structure. Due to their identical structural main motif Cu(CH3COO)2·H2O and Cu(CH3COO)2 exhibit a similar bluish‐green color, almost identical UV/Vis spectra and comparable magnetic properties. The temperature dependent magnetic susceptibility also indicates only weak inter‐dimer spin exchange between neighbouring Cu2(CH3COO)4 paddle wheels. [ABSTRACT FROM AUTHOR]

The thermal dissociation of gaseous Mo(CO)6 and W(CO)6 in an argon carrier gas, Mo(CO)6 → Mo(CO)5 + CO (1) and W(CO)6 → W(CO)5 + CO (2), is studied over temperature ranges of ∼585–685 K for (1) and ∼690−810 K for (2) at a total gas concentrations of 4 × 10−6 and 4 × 10−5 mol/cm3 by using the shock tube technique in conjunction with absorption spectrophotometry. The measured rate constants are extrapolated to the high‐pressure limit by means of a newly developed procedure, with the resultant expressions for the indicated temperature ranges reading as kd1,∞(T),[s−1] = 1016.12 ± 0.68exp[(−148.8 ± 8.1 kJ/mol)/RT] and kd2,∞(T),[s−1] = 1015.93 ± 0.63exp[(−171.7 ± 8.9 kJ/mol)/RT]. Comparison of the high‐pressure dissociation rate constants with the published data revealed a considerable discrepancy, a tentative explanation of which is given. Based on the obtained high‐pressure dissociation rate constants and the available data on the high‐pressure room‐temperature rate constants for the reverse reaction of recombination, the first bond dissociation energies for these molecules are evaluated and compared with previous determinations, both theoretical and experimental. The enthalpies of formation of Mo(CO)5 and W(CO)5 are determined: ΔfH°(Mo(CO)5, g,  298.15 K) = −644.1  ±  5.6 kJ/mol and ΔfH°(W(CO)5, g,  298.15 K) = −581.9  ±  6.6 kJ/mol. Based on the enthalpies of formation of Mo(CO)5, W(CO)5, Mo(CO)6, and W(CO)6, and the published molecular parameters of these four species, their thermochemical functions are calculated and presented in the form of NASA seven‐term polynomials. [ABSTRACT FROM AUTHOR]

The thermal dissociation of gaseous Mo(CO)6 and W(CO)6 in an argon carrier gas, Mo(CO)6 → Mo(CO)5 + CO (1) and W(CO)6 → W(CO)5 + CO (2), is studied over temperature ranges of ∼585–685 K for (1) and ∼690−810 K for (2) at a total gas concentrations of 4 × 10−6 and 4 × 10−5 mol/cm3 by using the shock tube technique in conjunction with absorption spectrophotometry. The measured rate constants are extrapolated to the high‐pressure limit by means of a newly developed procedure, with the resultant expressions for the indicated temperature ranges reading as kd1,∞(T),[s−1] = 1016.12 ± 0.68exp[(−148.8 ± 8.1 kJ/mol)/RT] and kd2,∞(T),[s−1] = 1015.93 ± 0.63exp[(−171.7 ± 8.9 kJ/mol)/RT]. Comparison of the high‐pressure dissociation rate constants with the published data revealed a considerable discrepancy, a tentative explanation of which is given. Based on the obtained high‐pressure dissociation rate constants and the available data on the high‐pressure room‐temperature rate constants for the reverse reaction of recombination, the first bond dissociation energies for these molecules are evaluated and compared with previous determinations, both theoretical and experimental. The enthalpies of formation of Mo(CO)5 and W(CO)5 are determined: ΔfH°(Mo(CO)5, g,  298.15 K) = −644.1  ±  5.6 kJ/mol and ΔfH°(W(CO)5, g,  298.15 K) = −581.9  ±  6.6 kJ/mol. Based on the enthalpies of formation of Mo(CO)5, W(CO)5, Mo(CO)6, and W(CO)6, and the published molecular parameters of these four species, their thermochemical functions are calculated and presented in the form of NASA seven‐term polynomials. [ABSTRACT FROM AUTHOR]

A new compound, Na(HINA)2(NH4)2[PMo10V2O40]·14H2O (1) (INA = isonicotinic acid) was synthesized and characterized structurally by elemental analysis, IR spectroscopy, and TG. Bisubstituted molybdovanadophosphate anions have typical Keggin anion structure and are linked weakly by Na+ ions into an anionic chain along crystallographic b axis. Protonated INA cations form another supramolecular cationic chain also along crystallographic b axis. Two chains, water molecules, and ammonium ions form the 3D supramolecular architecture through hydrogen bonds. The compound has an excellent catalytic activity to starch oxidation. The detailed study gives optimum reaction condition. [ABSTRACT FROM AUTHOR]

The subvalent nitridometalate Ba6[(Mo1–xTax)N4]N0.86 was prepared from mixtures of Mo powder with Ba, Na, and Ba2N at 600 °C in Ta ampoules. It crystallizes in space group Cmcm with a = 11.672(3), b = 10.177(2) and c = 10.8729(19) Å. Its crystal structure exhibits an orthorhombically distorted Perovskite topology with [Ba6N] building units forming the ReO3‐type lattice via common vertices, and the nitridometalate anions occupying half of the available distorted cuboctahedral interstices. [MN4] anions show statistically mixed occupancy of M by MoVI and TaV. They show no notable deviation from nitridometalate anions in known ionic nitridomolybdates and ‐tantalates, and the metrics of the [Ba6N] octahedra correspond to those found in similar subvalent compounds. The nitrogen atom position centering the [Ba6N] octahedra is underoccupied. Band structure calculations corroborate the subvalent character of the compound and the two individual anionic structural building units. [ABSTRACT FROM AUTHOR]

A highly efficient synthetic protocol for the synthesis of thia‐ and selenaheterocycles has been developed. By employing a MoCl5‐mediated intramolecular dehydrogenative coupling reaction, a broad variety of structural motifs was isolated in yields up to 94 %. The electrophilic key transformation is tolerated by several labile moieties like halides and tertiary alkyl groups. Due to the use of disulfide or diselenide precursors, a high atom efficiency was achieved. Molybdenum opens the door as pentachloride or as an anode material to synthesize a variety of thia‐ and selenaheterocycles in high yields up to 94 %. The dehydrogenative coupling of disulfides and diselenides leads to an excellent atom economy for the key transformation. [ABSTRACT FROM AUTHOR]

A continuous FeMo cofactor supply for nitrogenase maturation is ensured in Azotobacter vinelandii by developing a cage‐like molybdenum storage protein (MoSto) capable to store ca. 120 molybdate molecules (MoO42−) as discrete polyoxometalate (POM) clusters. To gain mechanistic insight into this process, MoSto was characterized by Mo and ATP/ADP content, structural, and kinetic analysis. We defined three functionally relevant states specified by the presence of both ATP/ADP and POM clusters (MoStofunct), of only ATP/ADP (MoStobasal) and of neither ATP/ADP nor POM clusters (MoStozero), respectively. POM clusters are only produced when ATP is hydrolyzed to ADP and phosphate. Vmax was ca. 13 μmolphosphate·min−1·mg−1 and Km for molybdate and ATP/Mg2+ in the low micromolar range. ATP hydrolysis presumably proceeds at subunit α, inferred from a highly occupied α‐ATP/Mg2+ and a weaker occupied β‐ATP/no Mg2+‐binding site found in the MoStofunct structure. Several findings indicate that POM cluster storage is separated into a rapid ATP hydrolysis‐dependent molybdate transport across the protein cage wall and a slow molybdate assembly induced by combined auto‐catalytic and protein‐driven processes. The cage interior, the location of the POM cluster depot, is locked in all three states and thus not rapidly accessible for molybdate from the outside. Based on Vmax, the entire Mo storage process should be completed in less than 10 s but requires, according to the molybdate content analysis, ca. 15 min. Long‐time incubation of MoStobasal with nonphysiological high molybdate amounts implicates an equilibrium in and outside the cage and POM cluster self‐formation without ATP hydrolysis. Databases: The crystal structures MoSto in the MoSto‐F6, MoSto‐F7, MoStobasal, MoStozero, and MoSto‐F1vitro states were deposited to PDB under the accession numbers PDB 6GU5, 6GUJ, 6GWB, 6GWV, and 6GX4. Polyoxomolybdate cluster storage of the molybdenum storage protein is separated into a rapid ATP hydrolysis‐dependent molybdate transport across the proteinous cage wall and a slow protein‐promoted and ATP‐independent molybdate self‐assembly process. Polyoxomolybdate clusters are formed in specific protein pockets supported by the high molybdate concentrations accumulated inside the cage provided via the molybdate pump. [ABSTRACT FROM AUTHOR]

Various morphologies of Cu2S and Cu2MoS4 were synthesized from an octahedral Cu2O template in the presence of various concentrations of sodium molybdate and thioacetamide by carrying out solvothermal reactions in an ethylene glycol solvent. The morphology varied from hollow octahedral Cu2S structures, through small pieces of P‐Cu2MoS4, and finally to thin square‐like plates of I‐Cu2MoS4, depending on the concentrations of sodium molybdate and thioacetamide. The XRD data indicated that the Cu2MoS4 structural phases changed from P4¯2m to I4¯2m the concentrations of sodium molybdate and thioacetamide increased. [ABSTRACT FROM AUTHOR]

The 2H molybdenum disulfide (MoS2), as a stable hexagonal phase, has been one of the most studied transition metal dichalcogenides over the past decades. In the last five years, the metastable phases of MoS2 (1T, 1T′, 1T′′, and 1T′′′) have seen a revival of interests. Different from the edge‐sharing [MoS6] trigonal prisms in the 2H MoS2 phase, these metastable phases are composed of the edge‐sharing [MoS6] octahedra, in which the neighboring Mo−Mo distances differ. Due to the various crystal structures and different electronic configurations of the building [MoS6] motifs, these metastable polytypes are endowed with intriguing physical properties and potential applications in diverse fields. In this Review, the recent research progress on metastable MoS2 is summarized, especially with an emphasis on the diverse synthetic approaches and the newly uncovered physical properties. The phase structures and electronic band structures are also outlined. In the end, a perspective of the future investigation on metastable MoS2 is discussed. S‐Mo‐S three atomic layers with different Mo−S coordination and Mo−Mo bonding result in diverse polymorphs of MoS2 monolayer, the stacking order of which determines the various polytypes of bulk MoS2 crystals. In this Review, the recent research progress on metastable MoS2 is summarized, with an emphasis on the diverse synthetic approaches and the newly uncovered physical properties. [ABSTRACT FROM AUTHOR]

Abstract: The high unsaturation of the title complex enabled it to react with a wide variety of molecules under mild conditions, whereby the agostic methyl ligand underwent unusual or unprecedented processes. Methane elimination occurred in the reactions with PPh2H and SiPh2H2, this being followed in the latter case by Si−H bond oxidative addition to give the hydride silylene derivative [Mo2Cp2H(μ‐PtBu2)(μ‐SiPh2)(CO)]. Dehydrogenation, however, was the dominant process in the room temperature reaction with [Fe2(CO)9], to give the unsaturated methylidyne cluster [Mo2FeCp2(μ3‐CH)(μ‐PtBu2)(CO)5] (Mo−Mo=2.6770(8) Å). In contrast, PMe elimination took place in the reaction with P4, to give the unsaturated triphosphorus complex [Mo2Cp2(μ‐η3:η3‐P3)(μ‐PtBu2)] (Mo−Mo=2.6221(3) Å). Yet a most remarkable reaction occurred with BH3⋅THF, involving insertion of two BH3 units and dehydrogenation to yield [Mo2Cp2(μ‐B2H4Me)(μ‐PtBu2)(CO)], with the novel methyldiboranyl ligand acting as a 5‐electron donor due to the presence of two 3‐centre, 2‐electron B‐H‐Mo interactions, according to spectroscopic data and DFT calculations (Mo−Mo ca. 2.65 Å). [ABSTRACT FROM AUTHOR]

New trinuclear molecules [Cu(meen)2]2[MoIV(CN)8]·5H2O (1) and [Cu(eten)2]2[Mo(CN)8]·7H2O (2) (meen = N‐methyl‐ethylenediamine; eten = N‐ethyl‐ethylenediamine) have been prepared and characterised by X‐ray diffraction and dc magnetometry. The crystal structure of 1 and 2 consists of trinuclear Cu2Mo molecules interacting through weak semicoordination bonds and resulting in the formation of 2D and 3D supramolecular networks, respectively. In the ground state, both molecules exhibit simple paramagnetic behaviour, with very weak antiferromagnetic interaction present at low temperatures. The photomagnetic studies of 1 and 2, performed using 436 nm light, have shown a significant increase in the magnetisation upon irradiation that might be explained in terms of a singlet–triplet transition at MoIV. [ABSTRACT FROM AUTHOR]

Abstract: Mixed valence/metal polyoxometalate (POM) clusters are one of the most interesting host species because they show the ability to incorporate a wide range of heteroatoms of various charges and geometries. We report herein the incorporation of pyramidal EO32− heteroanions (E=PH, S, Se, Te) that are responsible not only for directing the templated assembly of a family of mixed‐metal POMs but also for the symmetry‐breaking of the traditional Dawson architecture and modulation of the electronic characteristics of the cluster's shell. The isolated family of POMs consists of four members: (Me2NH2)5Na2[Mo11V7O52(HPO3)]⋅MeOH⋅5 H2O (1), (NH4)7[Mo11V7O52(SO3)]⋅12 H2O (2), K7[Mo11V7O52(SeO3)] ⋅31 H2O (3), and (Me2NH2)6Na[Mo11V7O52(TeO3)]⋅15 H2O (4), and were characterized by X‐ray structural analysis, electrospray ionization mass spectrometry (ESI‐MS), thermogravimetric analysis (TGA), UV/Vis, FTIR, elemental analysis, flame atomic absorption spectroscopy (FAAS), and inductively coupled plasma optical emission spectroscopy (ICP‐OES). Cyclic voltammetry (CV) and electron paramagnetic resonance (EPR) spectroscopic studies in concert with density functional theoretical (DFT) calculations have been used to elucidate the effect of the heteroatom on the electronic properties of the cluster. [ABSTRACT FROM AUTHOR]

TiO2 thin films with various Mo concentrations have been deposited on glass and n‐type silicon (100) substrates by this radio‐frequency (RF) reactive magnetron sputtering at 400°C substrate temperature. The crystal structure, surface morphology, composition, and elemental oxidation states of the films have been analyzed by using X‐ray diffraction, field emission scanning electron microscopy, atomic force microscopy, and X‐ray photoelectron spectroscopy, respectively. Ultraviolet‐visible spectroscopy has been used to investigate the degradation, transmittance, and absorption properties of doped and undoped TiO2 films. The photocatalytic degradation activity of the films was evaluated by using methylene blue under a light intensity of 100 mW cm−2. The X‐ray diffraction patterns show the presence of anatase phase of TiO2 in the developed films. X‐ray photoelectron spectroscopy studies have confirmed that Mo is present only as Mo6+ ions in all films. The Mo/TiO2 band gap decreases from ~3.3 to 3.1 eV with increasing Mo dopant concentrations. Dye degradation of ~60% is observed in Mo/TiO2 samples, which is much higher than that of pure TiO2. [ABSTRACT FROM AUTHOR]

The synthesis of an organoammonium diphosphopentamolybdates(VI), (C6H14N)5[HP2Mo5O23]·4H2O (1), is reportet. The molecular structure and spectroscopic analysis were performed using experimental techniques like X-ray diffraction, FT-IR, and UV/Vis. The single crystal analysis of the title compound shows that the compound crystallizes in the monoclinic crystal system with space group P21/c and cell constants of a = 12.7934(2) Å, b = 14.8145(2) Å, c = 27.2637(5) Å, and β = 92.9298(14)°. The Hirshfeld surfaces and the associated 2D fingerprint plots were investigated to study the intermolecular interactions in the crystal packing and this study has confirmed that the hydrogen bonding interactions play a dominating role in the stability of crystal structure. The theoretical calculations were done using PM3 semi-empirical model and several properties were studied. [ABSTRACT FROM AUTHOR]

A series of new cyclopentadienyl molybdenum compounds bearing substituted phenanthroline ligands [(η5-C5H4CH2C6H4X-4)Mo(CO)2(N,NL)][BF4] (X = F, Cl, Br; N,NL = phen, 5-NH2-phen, 4,7-Ph2-phen) was prepared and characterized using infrared and NMR spectroscopies. Crystal structures of [(η5-C5H4CH2C6H4F-4)Mo(CO)2(NCMe)2][BF4], [(η5-C5H4CH2C6H4X-4)Mo(CO)2(phen)][BF4] (X = F, Cl, Br) and [(η5-C5H4CH2C6H4Cl-4)Mo(CO)2(4,7-Ph2-phen)][BF4]⋅(4,7-Ph2-phen)⋅HBF4 were determined using X-ray diffraction analysis. Biological studies revealed a strong cytotoxic effect of the chelating ligands. Although the cytostatic effect of the halogen in the side chain of the cyclopentadienyl ring is negligible, it could be used for future post-modification of these types of cytotoxic active molybdenum-based compounds. [ABSTRACT FROM AUTHOR]

An approach to design Ga2O3-based nanomaterials with tunable mechanical properties is presented. In the molybdenum (Mo) incorporated Ga2O3 model system, where Mo content ( x) is varied up to ≈11 at%, Mo-incorporation induced effects are significant on the structural and mechanical properties. Single-phase β-Ga2O3 formation occurs for lower Mo content (≤4 at%); however, higher Mo content induces the crystalline-to-amorphous structural transformation. Mechanical characterization reveals that the hardness of the Ga-Mo-O nanocrystalline films increases for Mo ≤ 10 at%, at which point hardness decreases due to Mo-induced structural transformation. However, the elastic modulus of Ga-Mo-O decreases continuously with Mo incorporation. The Ga-Mo-O exhibits maximum H (≈36 GPa) for 10 at% Mo, where Mo-incorporation induces enhancement in hardness as well as plasticity index parameter. Based on the results, a structure-composition-mechanical property correlation in Ga-Mo-O films is established. [ABSTRACT FROM AUTHOR]

The homobimetallic molybdenum(VI) complex, [(MoO2)2(slsch)(DMF)2], derived from multidentate hydrazone ligand (H4slsch = disalicylaldehyde succinoyldihydrazone) was synthesized. The complex was obtained by reaction of the ligand with Mo2(acac)2 in 1:2 molar ratio in methanol. It was characterized by using various spectroscopic techniques. The structure of the complex was established by single crystal X-ray diffraction. The complex shows fluorescence emission, responds toward AlIII ions, and hence it can be used as fluorescence chemosensor for sensing AlIII ions. The sensing properties show that the complex is more efficient and sensitive towards AlIII ions than the rest of the ions used in the presented study. [ABSTRACT FROM AUTHOR]

Aminophosphine [Mo3S4X3(edpp)3]+ cluster complexes, 1+ (X = Cl) and 2+ (X = Br) {edpp = (2-aminoethyl)diphenylphosphine} have been quantitatively prepared by treating the [Mo3S7X6]2- anion with the edpp ligand in a one-pot synthetic procedure. Alternatively, complexes 1+ and 2+ can be synthesized using polymeric {Mo3S7X4} n phases as metal precursors. Their crystal structures show the incomplete cubane-type Mo3S4 cluster core as well as the formation of a unique isomer in which the nitrogen atoms of the amino group and the halide atoms are located above the trimetallic plane. Gas-phase reactivity studies on complexes 1+ and 2+ show the subsequent elimination of neutral HX (X = Cl, Br) molecules under collision induced dissociation (CID) conditions. The fragmentation pattern of 1+ and 2+ in combination with gas-phase DFT calculations are contrary to the general ideas involving the hemilabile character of the aminophosphine ligands and give support to the formation of unsaturated molybdenum/imine Mo=NH species. On the basis of DFT calculations, two competitive mechanisms involving a proton transfer from the amino group to a halide ligand attached to the geminal or to the vicinal molybdenum center are proposed. The first mechanism, which is a proton transfer within the nitrogen and halogen atoms bound to the same metal atom, is energetically favored from a theoretical point of view. [ABSTRACT FROM AUTHOR]

The role of the crystalline phase of Mo3VO x in the catalytic oxidation of allyl alcohol over four kinds of crystalline (orthorhombic, trigonal, tetragonal, amorphous) Mo3VO x catalysts was investigated to determine the active sites for the reactions. Tetragonal Mo3VO x was found less active for the formation of acrylic acid from allyl alcohol, although acrolein was obtained selectively at higher temperature. For orthorhombic and trigonal Mo3VO x catalyst, allyl alcohol converted to acrolein and propanal competitively at the mouth of the heptagonal channel over the a- b plane of the rod-type crystalline particles, and these aldehydes were oxidized consecutively to acrylic acid. Acrylic acid was formed effectively at increased reaction temperature over orthorhombic, trigonal and amorphous Mo3VO x catalysts, and the maximum yields of acrylic acid were 73 % for the orthorhombic Mo3VO x catalyst and 72 % for the trigonal Mo3VO x catalyst at 350 °C. [ABSTRACT FROM AUTHOR]

Salicylhydroxamic acid (H3shi) is known for its strong coordination ability and multiple coordination modes, and can easily coordinate to metal cations to form compounds with five- or six-membered rings, as well as mono-, di- and multinuclear compounds with interesting structures having potential applications in organic chemistry, coordination chemistry, and the materials and biological sciences. A novel octanuclear nickel(II)-molybdenum(VI) heterometallic cluster based on the salicylhydroxamate ligand, namely di-μ3-acetato-di-μ2-acetato-di-μ3-hydroxido-di-μ3-oxido-tetraoxidooctakis(pyridine-κ N)bis(μ5-salicylhydroxamato)hexanickel(II)dimolybdenum(VI) monohydrate, [Mo2Ni6(C7H4NO3)2(C2H3O2)4O5(OH)2(C5H5N)8]·H2O, (I), was synthesized by the reaction of sodium molybdate, nickel acetate and salicylhydroxamic acid in a dimethylformamide/pyridine/methanol solution at room temperature. The salicylhydroxamate(3−) (shi3−), acetate and oxide ligands adopt complicated coordination modes and link six NiII and two MoVI cations into the octanuclear heterometallic cluster. All of the metal cations exhibit octahedral coordination geometries and are connected to each other through the sharing of corners, edges or planes. The heterometallic clusters are further connected to form two-dimensional supramolecular layers through weak C-H...O hydrogen bonds. Studies of the magnetic properties of the title compound reveal antiferromagnetic interactions between the NiII cations. [ABSTRACT FROM AUTHOR]

The reaction of molybdenum, tungsten and manganese carbonyls with several thiazole heterocycle ligands yielded a number of coordinated transition metal complexes 1- 10. Of these complexes 1- 6 are new compounds which have not been reported to date. The structures of new compounds were characterized by FT-IR and 1H-NMR spectroscopy as well as single-crystal X-ray diffraction analysis. Complexes 1- 10 are carbon monoxide releasing molecules that show structure-related anti-cancer activity. The cytotoxicity of all compounds on Hela cells was evaluated by MTT assay, and the results show that carbon monoxide releasing molecules containing such Schiff base ligands may have biomedical applications for their anti-tumor effect. [ABSTRACT FROM AUTHOR]

The double molybdate Rb2Ba(MoO4)2 was synthesized by high temperature solid-state reaction. According to the single-crystal X-ray diffraction structure determination, it is isostructural to the mineral Palmierite K2Pb(SO4)2 in the trigonal space group R $\bar{3}$ m. Its structure can be described as layers of MoO4 tetrahedra corner-sharing with distorted BaO6 octahedra, while the layers are separated by bi-layers of rubidium cations in 10-coordinate environment. UV/Vis-NIR spectroscopy measurement indicates that Rb2Ba(MoO4)2 has an indirect bandgap of 4.40 eV, comparable to the calculated value 4.21 eV. The DSC test demonstrates the melting point and incongruent melting characteristic of the title compound. About seven narrow Raman lines were observed in the Raman spectrum recorded for Rb2Ba(MoO4)2 powder sample. [ABSTRACT FROM AUTHOR]

A series of six cis-dioxomolybdenum(VI) complexes with thiosemicarbazone ligands was synthesized and characterized. The ligands were obtained by reacting ethyl thiosemicarbazide with salicylaldehydes substituted with a selection of electron-withdrawing and electron-donating groups. The crystal structures, IR, NMR spectroscopic data and oxygen atom transfer activities of the complexes revealed that the electronic effects of the substituents located in the para-position of the phenolate donor are transmitted through to the molybdenum center, as reflected by linear relationships between Hammett constants and key properties of the complexes, including the molybdenum-phenolate bond lengths and the coordination shift of the imine proton resonance. Compared with the unsubstituted catalyst, electron-withdrawing substituents increase the rate of oxygen atom transfer from dimethyl sulfoxide to triphenylphosphine, whereas electron-donating groups have the opposite effect. The highest rate enhancement was achieved through the introduction of a strongly electron-withdrawing NO2 substituent in the p-position of the phenolate donor. [ABSTRACT FROM AUTHOR]

The development of a new solvochemical synthesis route resulted in single crystals of lanthanoid(III) fluoride oxidomolybdates(VI) with the formula LnF[MoO4] for the early lanthanoids ( Ln = Ce-Nd); to date, these compounds could not be obtained by solid-state reactions. The preparation strategy comprises the dropwise combination of an alkaline aqueous solution containing molybdenum trioxide, sodium hydroxide and sodium fluoride with an acidic aqueous solution of the lanthanoid(III) nitrate. After the purification of the obtained gel, the noncrystalline product has to be dried at 120 °C and converted into a crystalline phase by a final thermal treatment for 24 h at 850 °C in evacuated silica ampoules. The crystal structure of the lanthanoid(III) fluoride oxidomolybdates(VI) with formula LnF[MoO4] ( Ln = Ce-Nd) is not isotypic to those for the smaller rare-earth metals. The title compounds crystallize monoclinically in the space group P21/ n ( a = 703-694, b = 660-653, c = 939-933 pm and β ≈ 106°) with four formula units per unit cell. The structure contains crystallographically unique Ln3+ cations, which are surrounded by two F- and six O2- anions to form distorted bicapped trigonal prisms (CN = 8). These polyhedra are fused together by two common edges (e) consisting of two oxide anions to form ∞1{[ LnFOe4/2Ot2/1]6-} strands, which are finally condensed through shared fluoride vertices (v) to build up a three-dimensional ∞3{[ LnFv2/2Oe4/2Ot2/1]6-} network that still contains terminal (t) oxygen atoms. The Mo6+ cations reside in the tetrahedral voids of the aforementioned arrangement. This is the fundamental difference compared to the structures of the representatives with the smaller lanthanoids, in which the Mo6+ cations interconnect anionic ∞2{[ LnFe2/2Oe4/2Ot2/1]6-} layers to achieve their tetrahedral oxygen coordination spheres. Vibrational spectroscopic measurements such as bulk solid-state and single-crystal Raman spectroscopy as well as diffuse reflectance spectroscopy (DRS) were performed for the crystalline lanthanoid(III) fluoride oxidomolybdates(VI) and the noncrystalline samples of the dried raw products. [ABSTRACT FROM AUTHOR]

Reactions of monooxidized thioyl and selenoyl bis(phosphanyl)amine ligands C10H7-1-N(P( E)Ph2)(PPh2) [ E = S ( 1), Se ( 2)] with Mo(CO)4(pip)2 and W(CO)4(cod) afforded the complexes [ M(CO)4{ 1-κ2 P,S}] [ M = Mo ( 3), W ( 4)] and [ M(CO)4{ 2-κ2 P,Se}] [ M = Mo ( 5), W ( 6)]. Complexes 3- 6 were characterized by multinuclear NMR (1H, 13C, 31P, and 77Se NMR) and IR spectroscopy. Crystal-structure determinations were carried out on 3, 5, and 6, which represent the first examples of structurally characterized complexes of such ligands with group-6 metal carbonyls. [ABSTRACT FROM AUTHOR]

In the quest to discover the properties of planar semiconductors, two-dimensional molybdenum trioxide and dichalcogenides have recently attracted a large amount of interest. This family, which includes molybdenum trioxide (MoO3), disulphide (MoS2), diselenide (MoSe2) and ditelluride (MoTe2), possesses many unique properties that make its compounds appealing for a wide range of applications. These properties can be thickness dependent and may be manipulated via a large number of physical and chemical processes. In this Feature Article, a comprehensive review is delivered of the fundamental properties, synthesis techniques and applications of layered and planar MoO3, MoS2, MoSe2, and MoTe2 along with their future prospects. [ABSTRACT FROM AUTHOR]

Mono-oxo-bis-dithioveratrol-molybdate was synthesized, structurally characterized, and investigated with respect to its oxo-transfer activity. The latter was compared with the activity of the analogous tungsten complex. The title complex is a structural model for molybdopterin bearing arsenite oxidase and both complexes catalyze oxo-transfer reactions successfully to 100 % conversion. With the dithioveratrol ligand the oxidation of triphenylphosphine proved to be faster for the tungsten complex, which is untypical. The solid-state structure of the molybdenum complex exhibits an unexpected and very unusual polymeric structural motif consisting of the complex anion mono-oxo-bis-dithioveratrol-molybdate, sodium cations, and methanol. Infinite double-decker strands are formed with sodium bridges between the ether functions of two ligands in one strand and the Mo=O moiety of the second strand. [ABSTRACT FROM AUTHOR]

MoVI complexes with novel ditopic diaminotetraphenol ligands have been prepared by using a one-pot procedure in methanol or DMSO with [MoO2(acac)2] (acac = acetylacetonate) as the molybdenum source. The complexes were characterised with X-ray diffraction, NMR spectroscopic studies, elemental analysis and IR spectroscopy. In the solid state, the compounds represent either a rodlike molecular or oxido-bridged polymeric structure. The catalytic activity of the complexes was investigated by oxidising benzyl alcohol and 1-phenylethanol with hydrogen peroxide to the corresponding aldehyde and ketone, respectively. Furthermore, the catalytic activity was surveyed also in epoxidation of cyclooctene. [ABSTRACT FROM AUTHOR]

The reaction of Ph3SnCl, (R4N)2[Mo6O19] and (R4N)OH in a molar ratio of 6:1:10 leads to the formation of (R4N)[(Ph3Sn)MoO4] (R = nPr ( 1), nBu ( 2)). Compounds 1·CH3CN and 2 have been charactarized by IR spectroscopy and single crystal X-ray diffraction. 1·CH3CN forms orthorhombic crystals, space group P212121 with a = 1339.9(2), b = 1508.9(2), c = 1733.2(3) pm. 2 crystallizes in the monoclinic space group P21 with a = 1342.6(2), b = 2280.3(4), c = 1344.0(2) pm, β = 118.34(1). Both compounds 1 and 2 consist of isolated R4N+ cations and polymeric $\rm^{1}_{\infty}$[(Ph3Sn)MoO4]- chains with an alternating arrangement of Ph3Sn+ and MoO42- groups. Treatment of (Ph3Sn)2MoO4 with bis(ethylenediamine)copper(II) succinate yields [Cu(en)2(Ph3Sn)2(MoO4)2] ( 3). The zinc derivative [Zn(en)2(Ph3Sn)2(MoO4)2] ( 4) is obtained similarly by reaction of (Ph3Sn)2MoO4 with bis(ethylenediamine)zinc(II) formiate. Compounds 3·2DMF ·EtOH and 4·2DMF ·EtOH crystallize in the monoclinic space group P21/ n with a = 1998.0(2), b = 1313.3(1), c = 2181.6(2) pm, β = 90.97(1)° for 3 and a = 2015.4(1), b = 1316.7(1), c = 2157.0(1) pm, β = 90.40(1)° for 4. Like in the cases of 1 and 2, polymeric $\rm^{1}_{\infty}$[(Ph3Sn)MoO4]- chains are observed. The [M(en)2]2+ units (M = Cu, Zn) act as linkers between the $\rm^{1}_{\infty}$[(Ph3Sn)MoO4]- chains to give 2D layer structures with (6, 3) net topology. [ABSTRACT FROM AUTHOR]

Reactions of the thiocarbamoyl-molybdenum complex [Mo(CO)2(η2-SCNMe2)(PPh3)2Cl] 1, and ammonium diethyldithiophosphate, NH4S2P(OEt)2, and potassium tris(pyrazoyl-1-yl)borate, KTp, in dichloromethane at room temperature yielded the seven coordinated diethyldithiophosphate thiocarbamoyl-molybdenum complexe [Mo(CO)2{η2-S2P(OEt)2}(η2-SCNMe2)(PPh3)] β-3, and tris(pyrazoyl-1-yl)borate thiocabamoyl-molybdenum complex [Mo(CO)2(η3-Tp)(η2-SCNMe2)(PPh3)] 4, respectively. The geometry around the metal atom of compounds β-3 and 4 are capped octahedrons. The α- and β-isomers are defined to the dithio-ligand and one of the carbonyl ligands in the trans position in former and two carbonyl ligands in the trans position in later. The thiocabamoyl and diethyldithiophosphate or tris(pyrazoyl-1-yl)borate ligands coordinate to the molybdenum metal center through the carbon and sulfur and two sulfur atoms, or three nitrogen atoms, respectively. Complexes β-3 and 4 are characterized by X-ray diffraction analyses. [ABSTRACT FROM AUTHOR]

Reactions of the thiocarbamoyl-molybdenum complex [Mo(CO)2(η2-SCNMe2)(PPh3)2Cl] 1, and ammonium diethyldithiophosphate, NH4S2P(OEt)2, and potassium tris(pyrazoyl-1-yl)borate, KTp, in dichloromethane at room temperature yielded the seven coordinated diethyldithiophosphate thiocarbamoyl-molybdenum complexe [Mo(CO)2{η2-S2P(OEt)2}(η2-SCNMe2)(PPh3)] β-3, and tris(pyrazoyl-1-yl)borate thiocabamoyl-molybdenum complex [Mo(CO)2(η3-Tp)(η2-SCNMe2)(PPh3)] 4, respectively. The geometry around the metal atom of compounds β-3 and 4 are capped octahedrons. The α- and β-isomers are defined to the dithio-ligand and one of the carbonyl ligands in the trans position in former and two carbonyl ligands in the trans position in later. The thiocabamoyl and diethyldithiophosphate or tris(pyrazoyl-1-yl)borate ligands coordinate to the molybdenum metal center through the carbon and sulfur and two sulfur atoms, or three nitrogen atoms, respectively. Complexes β-3 and 4 are characterized by X-ray diffraction analyses. [ABSTRACT FROM AUTHOR]

Treatment of the cluster compounds [Cp2(CO)4Mo2 ESbCl] ( E = S, Se) with GaCl3 in thf as solvent leads to the compounds [Cp2(CO)4Mo2 ESb]GaCl4. [Cp2(CO)4Mo2SSb]GaCl4 crystallizes in the monoclinic system, space group P21/c with a = 815.64(6), b = 1094.31(5), c = 2503.7(2) pm, and β = 92.505(6)°. The selenium derivative [Cp2(CO)4Mo2SeSb]GaCl4 forms isotypic crystals with a = 811.53(4), b = 1103.90(6), c = 2511.2(1) pm, and β = 92.704(4)°. Both the derivatives display ionic structures consisting of separated [Cp2(CO)4Mo2 ESb]+ cations and GaCl4- anions. According to the 18 electron rule the [Cp2(CO)4Mo2 ESb]+ cations can be considered as electron precise tetrahedral clusters, which are closely related to the well-known dipnictogen complexes [Cp2(CO)4Mo2 E2] ( E = P, As, Sb, Bi). [ABSTRACT FROM AUTHOR]

Single crystals of the new β-variety of Na4Cu(MoO4)3 are prepared by firing a 4:1:3 molar mixture of Na2CO3, Cu(OAc), and (NH4)6Mo7O24 in air (porcelain crucible, 873 K, 20 d; cooling to 823 K at a rate of 10 K/d). [ABSTRACT FROM AUTHOR]

Single crystals (50 μm) of CsNbMoO6 (I) and CsTaMoO6 (II) are grown by spontaneous crystallization from melts of CsNO3, Nb2O5 (Ta2O5) and MoO3 in the molar ratio of 3:0.2:4, resp. [ABSTRACT FROM AUTHOR]

Polycrystalline Cs2CuxMo12Se14 (x = 0, 0.5, 1.0, 1.5, 2.0) phases are prepared by reacting stoichiometric amounts of Cs2Mo6Se8, Mo, and MoSe2 under Ar (sealed Mo crucible, 1573 K, 40 h) followed by reacting Cu powder with the as-prepared material (evacuated silica tubes, 1173 K, 48 h). [ABSTRACT FROM AUTHOR]