A spent vanadium catalyst was leached in an oxalic acid solution to recover vanadium, potassium and iron. The effects of time, temperature, acid concentration, phase ratio and catalyst particle size were studied. The results showed that for a 180–250 μm catalyst leached for 4 h at 323 K in the...

The fluoroolefin complexes Rh(dpm)(C2H4)(CF2CFX), (dpm = dipivaloylmethanato, X = F, CF3, Cl or Br) have been prepared. Triphenyl-phosphine, -arsine and -stibine displace ethylene from these complexes to give complexes of the type Rh(dpm)(CF2CFX)(L). 19F NMR studies are consistent with a str...

CoX(PPh3)3 (X Cl, Br, I) exhibits a fairly high catalytic selectivity in the presence of BF3-OEt2 for the hydrogenation of conjugated dienes such as 1,3-butadiene, 2-methyl-1,3-butadiene, and 1,3-pentadiene at ambient temperature and pressure to give 1-butene, 3-methyl-1-butene, and 1-pentene,...

Chlorotris(triphenylphosphine)rhodium, RhCl(PPh3)3 undergoes thermal decomposition above 140°C in solution and in the solid state to yield biphenyl. Rhodium complexes with para-substituted triphenylphosphine ligands form exclusively 4,4′-disubstituted biphenyls. Mixtures of two complexes RhCl(...

X-band electron paramagnetic resonance (EPR) studies of Cr3+ doped lithium potassium sulphate single crystals have been done at room temperature. The Cr3+ crystal field and spin Hamiltonian parameters have been evaluated by employing resonance line positions observed in the EPR spectra for diffe...

Electron paramagnetic resonance (EPR) and optical absorption studies of VO2+ doped lithium potassium sulphate single crystals are carried out at room temperature. The angular variation of the spectra is studied in the crystallographic a*b, bc and ca* plane. Vanadyl is found to have fixed orienta...

Thermal analysis of metal sulfate hydrazinates, MSO4·xN2H4 (I) (MMn, Co, Ni, Zn, Cd; x = 2–3), hydrazinium metal sulfates, (N2H5)2M(SO4)2 (II) (MMn, Cu, Zn, Cd), and N2H5LiSO4 have been studied using simultaneous TG-DTGDTA. Both types of complexes, I and II, decompose to the respective met...

The normal mode frequencies of the isotopically-substituted hydrazinium (2+) species N2DXH6−X (X = 1, 2…6) have been calculated using ab initio methods. The normal mode frequency shifts exhibit a wide range of dependence on the level of isotopic substitution and the nature of the normal mode. T...

The temperature dependence of several low frequency external modes of lithium hydrazinium sulfate have been examined. The temperature dependent bandwidth and frequency of the 53 cm−1 mode have been studied over the temperature range 11–300 K. The significance of breaks observed in plots of spec...

A novel technique for studying the basic mechanism of proton transport in hydrogen-containing solids is described. In this technique, which is termed “proton injection”, the hydrogen-containing material (here, lithium hydrazinium sulfate) is utilized as the electrolyte in an electrochemical ce...

The paper reports the results of detailed studies of the molecular structure of lithium hydrazinium sulphate single crystal in a wide temperature range with the aim to clarify previously reported anomalies in the molecular dynamics at ∼100 K. The crystal does not undergo any structural phase tr...

The low temperature polarized Raman spectra of lithium hydrazinium sulfate, LiN2H5SO4, have been measured in the range 5–3500 cm−1. The symmetry-based assignments for the observed modes are given. The room temperature polarized i.r. reflectivity spectra in the range 200–4000 cm−1 were also mea...

Polarized Raman scattering spectra are measured over a temperature interval from 15 to 300 K in single crystal lithium hydrazinium sulfate. No unusual temperature-dependent behavior is observed in any mode involving hydrazinium ion translatory motion, but all librational modes and the internal m...

The temperature dependence of the phase memory time TM in γ-irradiated lithium hydrazinium sulphate, LiN2H5SO4, single crystal has been measured in the temperature range 4.2–290 K. Two minima in TM(T) at 115 and 175 K were observed. The low-temperature TM minimum has been identified as due to ...

Publisher SummaryPolynuclear complexes with hydroxide (or oxide) as bridging ligands constitute an important class of complexes. They are formed by hydrolysis of mononuclear aqua complexes of most metal ions and, therefore, constitute an important aspect of the hydrolytic chemistry of metal ions...

Convenient and rapid preparative methods for a number of complexes of rhodium (III) are described, using the accessible trans-dihalotetrapyridinerhodium (III) salts as starting materials. A number of new compounds are characterized, and some reactions are discussed. A case of synergic solubility...

Comparison of the infra-red spectra of trans dichloro bis ethylenediamine cobalt (III) as the chloride and as the chloride hydrochloride dihydrate, and of trans dibromo bis ethylenediamine cobalt (III) as the bromide and as the bromide hydrobromide dihydrate indicates the presence of the hydroxo...

The substitution reactions of the 2,2′-biquinoline (biq) complex cis-[Rh(biq)2Cl2]Cl with Br−, I−, OH−, NH3, pyridine (py), CN−, NO2−, SCN−, ethylenediamine (en), 2,2′-bipyridine (bipy) and dimethylglyoxime (dmgmH2) have been investigated. The new complexes cis-[Rh(biq)2ICl]I, cis-[Rh(biq)2(OH...

The synthesis of complexes of the type trans-[RhL4X2]+ {L =N-alkylimidazoles (N-RIm) [R = methyl (Me), ethyl (Et), n-propyl (Pr0, n-butyl (Bun)], 4(6)-hydroxypyrimidine (4(6)-hydPm); X = Cl− or Br−) is achieved by the general catalytic method involving the use of ethanol. The formation of comple...

The substitution reactions of the title complex cis-[Rh(pq)2C12]Cl with I−, ethylenediamine (en), 2,2′-bipyridine (bipy), the oxalate dianion (ox), pyridine (py) and NO2− have been investigated. The new complexes cis-[Rh(pq)2ICl]I·2H2O, [Rh(pq)(H2O)(en)Cl](PF6)2, [Rh(pq)2(bipy)](PF6)3·2H2O, [...