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Cyclopentadienyl cobalt complexes have been known since 1953. In the recent years, they have attracted attention of chemists due to their application in C–H activation reactions. The review covers the synthesis of cyclopentadienyl cobalt(III) complexes with diverse auxiliary ligands (such as carbonyl, halides, solvents, arenes, amines, phosphines etc.) as well as their catalytic activity. The influence of auxiliary ligands on the catalytic activity is discussed.

Thin epitaxial Pb1−xCdxSe films with cadmium content x ≤ 0.36 have been grown by molecular beam epitaxy (MBE) on highly resistive, lattice matched (0 0 1) ZnTe/GaAs hybrid substrates. The High Resolution X-ray Diffraction (HRXRD) indicates that the films crystallize in the rock salt structure. Up to x = 0.12 the Pb1−xCdxSe films are (0 0 1) oriented and monocrystalline with negligible amount of other phases. The lattice constant of the films decreases proportionally to the Cd content. As evidenced by low-temperature photoluminescence (PL) the energy gap of Pb1−xCdxSe films increases with the increasing Cd content. The parameters of optical phonons and plasmons in the material are established by infrared reflectance measurements. The most interesting property of the Pb1−xCdxSe films is revealed by classical transport measurements. The alloying of PbSe with CdSe reduces the hole concentration in the material from a typical value of 3 × 1018 cm−3 in the pure PbSe film down to 3 × 1016 cm−3 in the film containing x = 0.052 of Cd. The reduction of the hole concentration by two orders of magnitude makes the Pb1−xCdxSe films very attractive for infrared detector applications. Simple photoresistors made of Pb1−xCdxSe films exhibit sensitivity to the infrared radiation up to the room temperature.

The aim of this paper is to develop an effective finite volume method for numerical simulation of the adiabatic shear bands (ASB) formation processes. A formation of ASB happens at high-speed shear strains of ductile materials. A numerical simulation of such problems using Lagrangian approach is associated with some problems, the main one of which is a mesh distortion at large deformations. We use Eulerian approach to describe a motion of the non-linear elasto-plastic material. More specifically, we consider a modification of a well-known hypoelastic Wilkins model. In this paper we suggest a numerical method for modeling of high-speed shear deformations on two-dimensional meshes. The method is verified on the three test problems suggested by other authors.

Reaction of dimethylamine adduct of 1-methyl-3-borolene with [(C2H4)2RhCl]2 gives the triple-decker complex (η-C4H4BMe)Rh(μ-η:η-C4H4BMe)Rh(η-C4H4BMe) (1a) in 62% yield and trace amount (

The arene iridium complexes [(η5-C5R5)M(η6-PhX)](SbF6)2 (1a: R = H, X = CH=CHPh; 1b: R = Me, X = CH=CHPh; 2: R = Me, X = C≡CPh; 3: R = Me, X = 4-Me-1H-isochromen-1-one) were synthesized by the reactions of the halides [CpIrI2]n or [Cp*IrCl2]2 with trans-stilbene, tolan and 3-phenyl-4-methyl-1H-isochromen-1-one in the presence of AgSbF6. They have proved to be stable towards the arene replacement with nucleophiles (such as acetonitrile, water and KI). The structures of 1b(SbF6)2 and 3(SbF6)2 were determined by X-ray diffraction. The experimental and DFT calculation data showed that the coordination of trans-stilbene and 3-phenyl-4-methyl-1H-isochromen-1-one with the Cp*Ir-moiety leads to the fluorescence quenching due to the intramolecular charge transfer from the ligand to iridium.

The Raman spectra of single crystalline RE (rare earth) tetraborides RE B 4 ( RE = Y, La, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Lu) are measured and analysed with respect to the dependence of the phonon frequencies on the rare earth metal. Phonons representing octahedral B 6 units are identified by comparison to the according phonon modes of hexaborides. Their relative force parameters are estimated.

The reaction of the thallium derivative [CpCo(μ-C3B2Me5)]Tl with [Rh(C2H4)2Cl]2 affords the μ-diborolyl bis(ethylene) triple-decker complex CpCo(μ-C3B2Me5)Rh(C2H4)2 (4). Structure of 4 was determined by X-ray diffraction. According to DFT calculations, the ethylene dissociation energies for the triple-decker complexes CpCo(μ-C3B2R5)Rh(C2H4)2 (R = H, Me) are ca. 6 kcal mol−1 lower than for cyclopentadienyl analogs (C5R5)Rh(C2H4)2. Energy decomposition analysis revealed that the bonding of anions [CpCo(C3B2R5)]− with [Rh(C2H4)2]+ is also weaker than that of [C5R5]−; the attractive interactions in both cases are 60–63% electrostatic and 37–40% covalent. The electrostatic potentials at the Rh nuclei suggest that the donor ability of the anions increases in the following order: Cp

The dimeric triple-decker type halides [CpCo(μ-1,3-C3B2Me5)MX2]2 (M = Rh, X = Cl, 1; M = Ir, X = Cl, 2; M = Rh, X = Br, 3; M = Ir, X = Br, 4) react with Me2SO and PPh3 giving adducts CpCo(μ-1,3-C3B2Me5)M(L)X2 (5–12). The Me2SO ligand is S-bonded to the metal atom in the solid state, while in acetone it is O-bonded. Structures of 5–12 were confirmed by X-ray diffraction.

The 86-electron dicationic octahedral rhodium clusters containing Cp (Cp = C5H5) ligands and either an interstitial carbon atom, [Rh6Cp6(μ6-C)]2+ ([1]2+), or two carbonyl groups, [Rh6Cp6(μ3-CO)2]2+ ([2]2+), were synthesized in low yields by reactions of Rh3Cp3(μ-CO)3 with RhCp(C2H4)2 or [RuCp∗(MeCN)3]+ (Cp∗ = C5Me5), respectively. The structures of [1]2+ and [2]2+ were determined by X-ray diffraction. Their electrochemical behavior proved that they possess a rather extended electron transfer activity. In accordance with DFT calculations, the nearly octahedral structure of [1]2+ and [2]2+ is retained both upon oxidation (2+/3+) and the first reduction (2+/+); however, the second reduction (+/0) results in the breaking of one (for [1]0) or two (for [2]0) Rh–Rh bonds. In the case of the related Dahl’s nickel cluster Ni6Cp6 the nearly octahedral structure is retained upon all redox steps (3+/2+/+/0/−/2−).

The B-phenylborole complex CpRh(η 5 -C 4 H 4 BPh) ( 1 ) reacts with [ML] + fragments to give the arene-type cationic complexes [CpRh(μ-η 5 :η 6 -C 4 H 4 BPh)ML] + (ML = RuCp ∗ ( 3 ), Co(C 4 Me 4 ) ( 4 ), Rh(cod) ( 5 ), and Ir(cod) ( 6 )). Cation 4 undergoes a reversible rearrangement into the triple-decker complex [CpRh(μ-η 5 :η 5 -C 4 H 4 BPh)Co(C 4 Me 4 )] + ( 7 ) under visible light irradiation in CH 2 Cl 2 solution. DFT calculations revealed greater stability of arene-type complexes over triple-decker isomers. The structure of [ 3 ]BF 4 was determined by X-ray diffraction.

The (borole)iodide complex [(η 5 -C 4 H 4 BPh)RhI] 4 reacts with the carborane anion [Carb′] − (Carb′ = 9-SMe 2 -7,8-C 2 B 9 H 10 ) giving (Carb′)Rh(η 5 -C 4 H 4 BPh) ( 2 ). Reactions of 2 with dicationic fragments [LM] 2+ afford the μ-borole triple-decker complexes [(Carb′)Rh(μ-η 5 :η 5 -C 4 H 4 BPh)ML] 2+ [LM = Cp ∗ Ir ( 4 ), (Carb′)Rh ( 7 )] or the arene-type complexes [(Carb′)Rh(μ-η 5 :η 6 -C 4 H 4 BPh)ML] 2+ [LM = Cp ∗ Rh ( 3 ), (Carb′)Ir ( 8 )]. The structure of 4 (BF 4 ) 2 was determined by X-ray diffraction.

Triple-decker complexes with a bridging borole ligand (C4H4BPh)Rh(μ-C4H4BPh)ML (ML = RuCp, 2a; RuCp∗, 2b; FeCp∗, 3; Co(C4Me4), 4; Ir(cod), 5) were synthesized by stacking reactions of [Rh(C4H4BPh)2]− (1) with cationic [ML]+ fragments. The structures of 2a,b and (C4H4BPh)Rh(μ-C4H4BPh)Rh(C4H4BPh) (6) were determined by X-ray diffraction.

Background . Escherichia coli strains that cause cystitis posses virulence properties that facilitate their colonisation and persistence in the bladder. In Iran, despite the high number of the urinary tract infections, very few studies has been done to determine the role of these virulence properties in the pathogenesis of E. coli cyctitis. Patients and methods . Eighty-seven strains of E. coli , isolated from young adults with cystitis in Shiraz, Iran, were examined for the expression of type 1 and P-fimbriae, mannose resistant haemagglutination, haemolysin production, aerobactin-mediated iron uptake, O:K serotypes, biochemical phenotypes (BPTs) and their antibiotic susceptibility patterns. Results . Seventy-six percent of the strains expressed multiple virulence properties. There was a significant correlation between the presence of aerobactin and the expression of type 1 fimbriae. All P-fimbriated strains produced aerobactin with 50% of them also coexpressing haemolysin. Of the 29 different O:K serotypes identified, 42% belonged to serotypes not commonly found among European serotypes associated with UTI. Strains of O groups 4 and 6 expressed more virulence factors than the others. A high resistance against ampicillin, trimethoprim and cotrimoxasol was observed among the isolates with 53% of the isolates showing multiresistance to these three antibiotics. Certain BPTs were also found among O:K serotypes with some containing strains of the same virulence profile. Conclusion . We conclude that certain colonal groups of E. coli are commonly associated with cystitis in young adults in Iran with strains possessing a combination of aerobactin and type 1 fimbriae being the dominant ones and belonging to serotypes not commonly found in Europe. We also conclude that the multiple antibiotic resistant E. coli strains causing cyctitis are highly prevalent in this part of the country.

The benzene complex [(η6-C6H6)OsCl2]2 (1) was obtained in 97% yield from thermal or microwave-assisted reaction of Na2OsCl6 with 1,3-cyclohexadiene in aqueous ethanol. Further reaction of 1 with TlCp gives [CpOs(η6-C6H6)]PF6 in 75% yield. Treatment of [CpM(η6-C6H6)]PF6 (M = Ru and Os) with NaBH4 in wet THF affords the cyclohexadienyl complexes CpM(η5-C6H7) in almost quantitative yields. The structure of [CpOs(η6-C6H6)]BArF (BArF = [B((3,5-(CF3)2)C6H3)4]) was confirmed by X-ray diffraction.

The cationic complex [Cp*Ru(C5Me4CH2)]+ reacts with Et3N primarily giving the ammonium salt [Cp*Ru(C5Me4CH2NEt3)]+. The prolonged standing of the reaction mixture results in the formation of the ether Cp*Ru(C5Me4CH2OCH2C5Me4)RuCp*. The reaction of [Cp*Ru(C5Me4CH2)]+ with PhNEt2 leads to the electrophilic aromatic substitution product [Cp*Ru(C5Me4CH2C6H4NHEt2)]+.

To analyze the activation of ITER blanket structural components, the authors have prepared the AUCDAS code that calculates changes in nuclide concentrations and radioactivity characteristics during neutron irradiation and during cooling. UCDAS takes into account all neutron reactions and decay types, the prepared library of constants contains nuclear data of nuclides from hydrogen to californium. A comparative analysis of the results as obtained using UCDAS code and the widely known FISPACT code is given. The analysis of decay heat, gas generation and activity of ITER blanket first wall's structural components was carried out. The beryllium coating, copper alloy and stainless steel were analysed. Calculations were performed for the first plasma burning pulse, 6 months and 1 year of operation in accordance with the ITER scenario. The materials recommended by ITER central team and their Russian analogs were considered: TGR and B1 (beryllium coating), GlidCop AL-25 Ds and Br-MKX (copper alloy), 316LN-IG and 12Cr18Ni10Ti (stainless steel). It has been demonstrated that there is a difference in all of the considered characteristics between the above materials. It is caused by impurities which are present in the materials. The report also considers the accumulation of gases (H, D, T, He3,He4) in the above materials. Besides, the change in the activity of irradiated materials during the cooling of up to 107 years was calculated.

The behaviour of the three-membered metallacycle Cp 3 Rh 3 (μ-CO) 3 is similar to that of benzene and other benzenoids in reactions with 12-electron-particles CpM + (where M = Fe, Ru). Accordingly a hypothesis was made that Cp 3 Rh 3 (μ-CO) 3 behaves as a typical benzenoid system. Cationic half-sandwich and sandwich clusters were synthesized during the interaction of Cp 3 Rh 3 (μ-CO) 3 with cationic particles PPh 3 M + (where M = Cu, Ag, Au) and (CH 3 CN) 4 M + (where M = Cu, Ag).

Tetrahedral cationic cluster [MRH3(η-C5R5)(η-C5H5)3(μ3-CO)3]PF6 (M = Fe, R = H; M = Ru, R = H, Me) were synthesized by reaction of [Fe(η-C5H5)(η-Arene)]PF6 or [Ru(η-C5R5)(MeCN)3]PF6 with Rh3(η-C5H5)3(μ-CO)3. Their structure was confirmed by IR and NMR spectroscopy as well as by an X-ray diffraction study of [RuRh3(η-C5Me5)(η-C5H5)3(μ3-CO)3]PF6.

The μ-diborolyl triple-decker complex CpCo(μ-1,3-C3B2Me5)PtMe3 was prepared by reaction of the sandwich anion [CpCo(1,3-C3B2Me5)]–with [PtMe3I]4; according to energy decomposition analysis, attractive interactions between the [CpCo(1,3-C3B2Me5)]– and [PtMe3]+ fragments are ∼64% electrostatic and 36% covalent.

Novel mixed trigonal-bipyramidal clusters [MRh4(η-C5H5)4(PPh3)(μ3-CO)2]+PF6–(M=Cu, Ag, Au) have been prepared by the reaction of Rh4(η-C5H5)(μ,3-CO)2 with [M(PPh3)]+ fragments, generated in situ in CH2CI2 from M(PPh3)Hal.

A description of the Finnish-Soviet Fourier TOF neutron powder diffractrometer Mini-SFINKS is given. The facility has been used in its present configuration for a growing number of experiments since 1986. Some examples of these, including studies of high- T c superconductors, are given to illustrate the performance of the machine.