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The Fourier transform (FT)-Raman and infrared (IR) spectra of triphenyl-, perdeuterated triphenyl-, tris(2-methylphenyl)-, tris(3-methylphenyl)-, tris(2,4,6-trimethylphenyl)-, tris(2-methoxyphenyl)-, tris(3-methoxyphenyl)-, tris(3-fluorophenyl)- and tris(4-fluorophenyl)-arsine, -stibine and -bismuthine were measured in the range 3600-100 cm−1. A normal coordinate analysis was performed for all substances using a modified valence force field. This leads to an unique force field for these compounds, where only the metal depending force constants vary noticeably. It was also possible to find a relationship between the chemical nature and the position of the different substituent and the metal-carbon stretching force constant. For all substances 1H-NMR, 13C-NMR and MS data were also given.

The entitled quinone 4 reacts with triphenylphosphine (3a) and triphenylarsine (3b) to give the cyclic products 12a and 12b, respectively. The same quinone reacts with triphenylstibine (3c) to yield the stibine-methylene 17. The reaction of oxides of 3a-c (5a-c) and trialkyl phosphates 6a-c with the same quinone 4 affords hydrogen bonded complexes 13a-c and o-quinol monophosphates 23a-c, respectively. In both cases compound 22 is the other product. Possible reaction mechanisms are proposed to explain the formation of the new adducts.

The kinetics and mechanism of the reactions between trans-[PtI3(PPh3)]– and trans-[PtI3(SbPh3)]– with pyridine, 2- and 4-methylpyridine in acetonitrile solvent have been studied by stopped-flow spectrophotometry. The crystal and molecular structures of the tetrabutylammonium salts of the two anions have been determined. Substitution of iodide trans to stibine is reversible and takes place via parallel direct and solvolytic pathways; substitution in the phosphine complex occurs with negligible back reaction. The kinetic data indicate that triphenyl-stibine and -phosphine should be placed in a series of decreasing trans effect, C2H4 > SbPh3 > CO > P(OMe)3 > PPh3 > AsEt3, i.e. SbPh3 has a much larger trans effect than that of PPh3; stibine complexes in the present study react ca. 16 times faster than their phosphine analogues. The activation parameters are typical of associatively activated processes, and in the case of the stibine complex they indicate that very little bond breaking has occurred in the transition state. In the ground states there is a clear-cut difference in the Pt–I distances trans to the pnictogen, 2.637(2) A in the stibine complex and 2.662(3) A in the phosphine complex, indicating that SbPh3 has a smaller ground-state trans influence and hence is a weaker σ donor than PPh3. Since the kinetic trans effect is a combination of ground-state labilisation and transition-state stabilisation, it is concluded that the large trans effect of stibine is due to a better π acceptance. Based on a comparison of Sb–C distances and C–Sb–C angles in free and co-ordinated stibine, this is proposed to be due to a higher d character of the π* orbitals on stibine as compared to phosphine, leading to a better overlap between antimony π* and platinum 5d π orbitals.

The tritertiary stibine MeC(CH2SbPh2)3 (tts) reacted with [M(CO)6] (M = Cr, Mo, W) in ethanol in the presence of NaBH4 to form fac-[M(CO)3(tts)], which were characterized by analysis, IR spectrosco...

Tris(2,6-dimethoxyphenyl)arsine and tris(2,6-dimethoxyphenyl)stibine ( Φ 3 M( Φ = 2,6-(MeO) 2 C 6 H 3 ; M = As an Sb)) reacted with common alkyl halides (RX) to give [Φ 3 M-R]X, while Φ 3 Bi was unreactive in benzene, or it decomposed in hot alcohols. The reactions of Φ 3 M (As, Sb) with butyl bromide in acetonitrile were much faster than that of triphenylphosphine. Treatments of Φ 3 M (P, As, Sb)with N -bromosuccinimide (NBS) gave [Φ 3 M−OH]Br, while Φ 3 Bi decomposed to give 1-bromo-2,6-dimethoxybenzene. [Φ 3 M-OH]Br are soluble in water, and the acidity decreased in the order M = P > As > Sb. Treatments of Φ 3 M(As, Sb) with aqueous hydrogen peroxide gave the oxides as hydrates, φ 3 MO. x H 2 O ( x = 1, for M = As and x = 3 for M = Sb), while Φ 3 Bi was unreactive or decomposed. Φ 3 PO was brominated by NBS to give Φ 3 'PO.H 2 O ( Φ = 3-Br-2,6-(MeO) 2 C 6 H 2 ), which did not react with perchloric acid. In contrast, Φ 3 MO. x H 2 O (P, As, Sb) reacted with the acid to form the stable hydroxyonium salts [Φ 3 M−OH]ClO 4 . [Γ 3 POH]ClO 4 formed crystals of stable 1 : 1 adducts with a variety of amines. [Φ 3 AsOH]ClO 4 formed 1 : 1 adducts when treated with excess amounts of several amines (triethylamine, diethylamine, isobutylamine and piperidine), but they were unstable to leave amines by recrystallization. [Φ 3 SbOH]ClO 4 formed unstable adducts with these amines, or it did not form. [Φ 3 PSH]ClO 4 formed 1 : 1 adducts with several amines, or it was deprotonated to give Φ 3 MO. x H 2 O (P,As) reacted with common RX (X - Br or I) to give [Φ 3 M-OR]X, but but φ 3 SbO. 3H 2 O reacted to give Φ 3 SbOH]X. [Φ 3 POR]X decomposed reversibly to give Φ 3 PO in solutions, although [Φ 3 MOR]ClO 4 (P, As) could be recrystallized.

Stibine, generated by mixing a 0.7 M sulfuric acid solution of antimony(III)with a 2% sodium tetrahydroborate solution in a mixing coil for 30 s, was separated from solution in a gas-liquid separator, and then swept into an electrically heated quartz furnace by manipulating electromagnetic relays and timers.Sharp peaks were recorded on a recorder. The detection limit (three times signal to noise ratio) for antimony(III)was 0.6 ng ml-1.It took five minutes for one sample measurement.Interference from transition metals could eliminated by Chelex 100 separation.Antimony(V)was reduced by using a 0.1 M potassium iodide solution. The accuracy, checked with a biological standard reference material obtained from the National Institute of Standard and Technology (NIST) of USA, was within the certified value. Antimony in river water was determined by the present method.

Syntheses and isolations of the tris(amino)stibine and tris(amino)bismuthine E[N(H)(C(6)H(2)(t)Bu(3))](3) (E = Sb, Bi) from ECl(3) and LiN(H)(C(6)H(2)(t)Bu(3)) are described, together with spectroscopic and structural characterization [crystal data for C(54)H(90)N(3)Sb, M = 903.04, space group Ponemacr;, a = 11.491(5) Å, b = 24.652(7) Å, c = 10.002(5) Å, alpha = 98.38(3) degrees, beta = 96.44(5) degrees, gamma = 77.25(3) degrees, V = 2724(2) Å(3), D(c) = 1.101 Mg/m(3), Z = 2, R = 0.0547; crystal data for C(54)H(90)BiN(3), M = 990.27, space group Ponemacr;, a = 11.511(5) Å, b = 24.785(15) Å, c = 9.981(5) Å, alpha = 98.06(5) degrees, beta = 96.50(4) degrees, gamma = 77.40(5) degrees, V = 2742(2) Å(3), D(c) = 1.200 Mg/m(3), Z = 2, R = 0.0619]. The compounds bear the "bulky" 2,4,6-tri-tert-butylphenyl substituent (known as supermesityl or Mes), and their formation is considered in the context of the same reactions for PCl(3) and AsCl(3), which have been previously shown to produce the aminoiminopnictine structures [N(H)(C(6)H(2)(t)Bu(3))]P=N(C(6)H(2)(t)Bu(3)) and [N(H)(C(6)H(2)(t)Bu(3))]As=N(C(6)H(2)(t)Bu(3)). The observations establish the limits of the steric control by the supermesityl substituent and provide qualitative support for the thermodynamic significance of substituent steric strain.

The key features of arsines, stibines and bismuthines as ligands towards transition metal and main group metal/metalloids are described. Following a brief review of the development of the chemistry, the main synthetic routes to the ligands are described and the advantages and limitations of the various approaches outlined. Current views of the nature of the metal-ligand bonding are evaluated, and the main coordination modes of the ligands described with illustrative examples.

A sensitive, precise and automated non-chromatographic method for Sb(III) and Sb(V) analytical speciation based on a continuous tandem on-line separation device in connection with inductively coupled plasma-atomic emission (ICP-AES) detection is proposed. Two on-line successive separation steps are included into this method: a continuous liquid-liquid extraction of Sb(III) with ammonium pyrrolidine dithiocarbamate (APDC) into methylisobuthylketone (MIBK), followed by direct stibine generation from the organic phase. Both separation steps are carried out in a continuous mode and on-line with the ICP-AES detector. Optimization of experimental conditions for the tandem separation and ICP-AES detection are investigated in detail. Detection limits for Sb(III) were 3 ng.mL(-1) and for Sb(V) 8 ng.mL(-1). Precisions observed are in the range +/- 5%. The proposed methodology has been applied to Sb(III) and Sb(V) speciation in sea-water samples.

The cubic and quartic force fields of AsH 3 , SbH 3 , and BiH 3 are determined from ab initio calculations using effective core potentials and polarized double-zeta valence basis sets. The computed geometries, dipole moments, rotational constants, vibration-rotation interaction constants, l -doubling constants, anharmonicity constants, vibrational wavenumbers, centrifugal distortion constants, and Coriolis coupling constants are compared with the available experimental data for AsH 3 and SbH 3 . The vibrational wavenumbers and other spectroscopic constants for the BiH 3 molecule are predicted.

A one-pot stibine modified Co 2 (CO) 8 homogeneous catalytic reductive N-alkylation of primary amides using aldehydes/ketones as alkylating agents, is reported. Good to excellent yields of a wide range of secondary amides are obtained (up to 97%) under relative mild conditions.

The production of arsenic usually occurs as a by-product of copper smelting, and is approximately in the range of 50,000–100,000 tons per year but this is a rough estimate based on previous global estimates by WHO and the impact of increasing use of As in the global semiconductor industry. This element is used for a variety of industries including glass manufacturing, wood preservatives, metal alloys, pesticides and in the manufacture of semiconductors as a dopant for silicon-based semiconductors or the production of III-V semiconductors such a gallium arsenide and indium arsenide. Fowler's solution (potassium arsenite-As3+) had been used in the past to treat a variety of clinical illnesses such as leukemia and skin disorders such as psoriasis and bronchial asthma but was supplanted by more modern chemotherapeutic agents during the last 20 years. More recently, As3+ has been effectively used to treat promyelocytic leukemia. Human exposure to inorganic arsenic may occur via air, food, and water. Persons consuming seafood generally have higher total intakes of arsenic, but the chemical forms of arsenic are primarily arsenobetaine and other methylated species of relatively low toxic potential. Arsenic is a general systemic poison whose toxic and medicinal properties have been known for several thousand years. The carcinogenic properties of inorganic arsenicals in humans have been known for several hundred years. Sb as an element is a brittle, flaky, crystalline (hexagonal) silver-white metal. It does not react with air at room temperature but burns brightly when heated, and forms white fumes. It is a poor conductor of electricity and heat. Antimony occurs in tri- (+3) and pentavalent (+5) compounds and is found in the earth's crust mostly associated with sulfur as stibnite and in ores associated with arsenic. Antimony is a group VA element of the periodic table and it has many of the same chemical and biological properties as the element arsenic. Stibine gas is odorless. Exposure to antimony at high levels may result in a variety of adverse health effects. For example, breathing high levels of antimony and some of its compounds can irritate the eyes and lungs and can cause problems with the heart, lungs, and stomach. Historically, antimony compounds were used as emetics and expectorants. Recently, antimony compounds, such as tartar emetic and sodium stibogluconate, are used as antihelminthic and antiprotozoic drugs in treating parasitic diseases and infections. It plays no role in nutrition and is a nonessential element. Bismuth is a brittle, white, crystalline metal that has a pinkish tint. It is the most diamagnetic of all metals, and its thermal conductivity is lower than any metal except mercury. In addition, bismuth has high electrical resistance and the highest Hall effect of any metal. Inorganic salts of bismuth are poorly water soluble; solubility is influenced by the acidity of the medium and the presence of additional certain compounds containing sulfhydryl or hydroxyl groups. Bismuth belongs to the VA group of the periodic system together with arsenic and antimony, and it forms compounds in the +3 and +5 oxidation states. Bismuth occurs in the native form; however, it is found largely in nature in minerals such as bismite, bismuthinite, and bismutite and is usually associated with sulfide ores of lead and copper and tin dioxide. Human exposure to bismuth and bismuth compounds is quite limited, except for its use in medicine where it has been prescribed for more than a century. Occupational and environmental exposure to bismuth and its toxicological significance are still unknown. Keywords: Arsenic; Antimony; Bismuth; Arsenic compounds; Antimony compounds; Bismuth compounds; Physical and chemical properties; Production; Use; Toxic effects; Exposure assessment; Environmental impact; Standards; Regulations; Guidelines; Cancer; Skin; Excretion; Neurological effects; Gastrointestinal effects; Mann model; Hematological effects

Total antimony was determined by inductively coupled plasma atomic emission spectrometry (ICP AES) using hydride vapor generation. A1 g wet, 0.25 g dry, or 10 mL water sample was digested by one of 2 distinct methods in a 10 mL graduated Kimax culture tube on a programmed heating block by heating with nitric acid and then boiling in a mixture of sulfuric acid and perchloric acid. For soils, a 0.25 g sample was digested in a 10 mL volumetric culture tube with hydrochloric acid. After digestion, the samples were treated with hydrochloric acid and potassium iodide. The antimony was then reduced by sodium borohydride to stibine (SbH3) in a simplified, continuous-flow manifold. A standard pneumatic nebulizer effected the gas–liquid separation of SbH3, which was then quantified by ICP AES at 231.147 nm. The instrument detection limit was 0.41 μg/L. Recoveries from 10 matrixes were 80 to 100%, with a typical relative standard deviation of 5.3%. The digestion and analysis methods demonstrated statistical control for samples of environmental and biological interest and are especially well suited to analysis of small samples. This method requires no additional apparatus for hydride generation or sample introduction.

Reaction of triarylbismuthines 1 with iodosylbenzene in dichloromethane under ultrasonic irradiation leads to the generation of triarylbismuthine oxides 2 as a bright yellow solution, in which activated alcohols are easily oxidized to carbonyl compounds, triphenylphosphine is converted into oxide and hydrazobenzene is rapidly dehydrogenated to azobenzene. Triphenylstibine 8 is similarly oxidized to give stibine oxide 9 , which lacks the corresponding oxidizing ability.

Studies are reported of the electro-optical Kerr effect, electric dipole moments and IR carbonyl stretching frequencies of the nine EPh 3 (CO) 5 complexes (E  P, As or Sb and M  Cr, Mo or W). The experimental results are applied in conjunction with molecular mechanics calculations and data from X-ray crystal structure analysis, to explore the stereostructural preferences of the EPh 3 M(CO) 5 molecules with regard to orientations about the ME bond and phenyl group rotations about EC ar . Evidence is drawn together and compared for EPh 3 M(CO) 5 in the solution and solid states and as isolated molecules. It is found that for all states, phenyl ring dispositions of like helicity are favoured for the coordinated EPh 3 ligands in these complexes.

An InP0.88Sb0.12 layer has been epitaxially deposited onto an n+ InP:S substrate using a stibine (SbH3) gas generator and a conventional metalorganic vapor phase epitaxy (MOVPE) reactor. A 0.7 μm thick layer was deposited at a temperature of 600∘C in 30 min using 250 SCCM of PH3 and 0.07 SCCM of SbH3. The layer was characterized using X-ray diffraction, electron microprobe analysis, and SIMS.

The pentafluoronitrosobenzene C 6 F 5 NO has been shown from infrared spectral, 19 F NMR spectral and single-crystal X-ray diffraction studies to undergo oxidation at the para -position upon reaction with [OS 3 H(μ-H)(CO) 10 (PPh 3 )] to afford [OS 3 (μ-H)(CO) 10 (PPh 3 )(ONC 6 F 4 O)](I). The arsenic- and stibine- analogues of I [(OS 3 )(μ-H)(CO) 10 (MPh 3 )(XONC6F40)l (M = As, Sb)) were also isolated.

The synthesis of the common monodentate and bidentate stibines and bismuthines, and of multidentates containing one or more antimony or bismuth donor are briefly reviewed. The detailed coordination chemistries of SbH3, trialkyl- and triaryl-stibines and -bismuthines are described, followed by a treatment of distibine complexes and complexes of multidentates containing antimony (and rarely bismuth) in combination with other group 15 or 16 donors. The available X-ray structural data, antimony-121 Mossbauer results, and UV-visible data on these complexes are compiled. Throughout the article comparisons are drawn with complexes of lighter group 15 donor ligands and the considerable differences between stibine ligands and the more familiar phosphines and arsines are highlighted.

Tri(p-tolyl)antimony dibromide is synthesized by the oxidation of tri(p-tolyl)stibine with copper bromide CuBr2 in acetone. According to the X-ray diffraction analysis data, the antimony atom in tri(p-tolyl)antimony dibromide has the configuration of a trigonal bipyramid with axial bromine atoms. The Sb–Br and Sb–C bond lengths are 2.631(5) and 2.111(4) A, the CSbC and BrSbBr angles are 120° and 180°, and the intramolecular Br...C(1,2) contacts are 3.374 and 3.517 A, respectively.

Durch photochemische Umsetzung von (CO)3Fe[P(OPh)3]2 und von MeCpMn(CO)3 mit Anti-monliganden des Typs Ph2SbCl und (Ph2Sb)2X (X = O, S und CH2) konnen Einkernverbindungen (CO)2[P(OPh)3]2FeL und MeCp(CO)2MnL (L = Ph2SbCl, (Ph2Sb)2X sowie die uber Distibanliganden verbruckten Zweikernverbindungen (CO)2[P(OPh)3]2Fe{(Ph2Sb)2X}Fe(CO)2[P(OPh)3]2 und MeCp(CO)2Mn{(Ph2Sb)2X}Mn(CO)2MeCp synthetisiert werden. Complexes of Iron and Manganese with Oxygen-, Sulfur-, and Methylene-bridged Distibines and with Chlorodiphenylstibine as Ligands The photochemical reaction of CO3Fe[P(OPh)3]2 and of MeCpMn(CO)3 with the stibines Ph2SbCl and (Ph2Sb)2X (X = O, S and CH2) yields mononuclear complexes (CO)2[P(OPh)3]2FeL and °Cp(CO)2MnL (L = Ph2SbCl, (Ph2Sb)2X) and the stibine bridged binuclear complexes °CO)2[P(OPh)3]2Fe{(Ph2Sb)2X}Fe(CO)2[P(OPh)3]2 and °Cp(CO)2Mn{(Ph2Sb)2X}Mn(CO)2MeCp.

Photochemical reactions of complexes of the stoichiometric type M(NO)X3(Ph3Y)2 for MRu, Os; YP, As, Sb; XCl, Br, I and M(NO)X2(Ph3Y)2 for MRh, Ir; YP, As; XCl, Br, I, have been investigated. In many of the reactions one of the organo-pnictide ligands (Ph3Y) is oxidized and remains coordinated (through the oxygen) to the transition metal. In the case of rhodium and iridium complexes, however, different reactions occur with complete loss of NO from the metal centre. Oxidation studies of the free ligands, and mass spectrometric analysis of gaseous reaction products have been used to elucidate the nature of the oxidizing agent for the complexes. The photochemical reactions of the complexes Ru(NO)X3(Et2PhP)2 for XCr, Br, I have also been studied and they differ from the others in that isomerization occurs from the trans isomer to the cis-meridional isomer.

The primary and secondary trimethylsilylmethylstibines (trimethylsilylmethyl = Me3SiCH2-) (Me3SiCH2)SbH2 and (Me3SiCH2)2SbH have been synthesized by the reduction of a corresponding dihalo- and monohaloantimony compound, respectively. Trimethylsilylmethylstibine was prepared by the reduction of (Me3SiCH2)SbBr2 with lithium aluminum hydride (LAH) in tetraglyme. The primary stibine is highly air-sensitive and exhibits a vapor pressure of 2.0 Torr at O°C. Bis-(trimethyl-silylmethyl)stibine was synthesized by the LAH reduction of either (Me3SiCH2)2SbBr or (Me3SiCH2)2SbI in diethyl ether. The secondary stibine is less sensitive to air than (Me3SiCH2)SbH2 but nonetheless decomposes quickly when exposed to air. The detailed synthesis, spectroscopic characterizations and physical properties of both stibines, as well as the preliminary chemical vapor deposition experiments of (Me3SiCH2)SbH2, are discussed.

A high-resolution Fourier transform infrared spectrum of the second stretching overtone band of stibine, SbH 3 , near 5500 cm −1 has been rotationally analyzed in detail up to J′ = 18 using a model Hamiltonian which treats simultaneously the rotational levels of the two close-lying vibrational states A 1 and E. The vibrational energy level separation has been determined to be 0.0501 (7) cm −1 for 121 SbH 3 and 0.0499(8) cm −1 for 123 SbH 3 . According to the vibration—rotation parameters obtained stibine is near the local mode limit. The vibrational dependence of the effective vibration—rotation parameters has been reproduced well with a simple local mode model.

The non-iterative parametric approach to solving two-dimensional inverse vibrational problems is discussed with respect to the search for all multiple solutions. Symmetry force constants for acetylene, ethylene, methane, silane, germane, stannane and their deuterium isotopes, for carbon-12 and carbon-13 isotopes of tetrafluoromethane, as well as for ammonia, phosphine, arsine, stibine and their deuterium isotopes, are determined with high accuracy. Good agreement with force fields cited from other authors is observed. The results for the two-dimensional symmetry species of acetylene and ethylene are compared with results of the iterative method of isotopic molecular force constant invariance (B. Nikolova, Commun. Dep. Chem., Bulg. Acad. Sci., 21/2 (1988) 158).

Traces amounts of arsenic and antimony in water samples were determined by gas chromatography with a photoionization detector after liquidnitrogen cold trapping of their hydrides. The sample solution was treated with sodium hydroborate (NaBH4) under weak-acid conditions for arsenic(III) and antimony(III) determination, and under strong-acid conditions for arsenic(III+V) and antimony(III+V) determination. Large amounts of carbon dioxide (CO2) and water vapor obscured determination of arsine and stibine. Better separation from interference could be achieved by removing CO2 and water vapor in two tubes containing sodium hydroxide pellets and calcium chloride, respectively. The detection limits of this method were 1.8 ng dm−3 for arsenic and 9.4 ng dm−3 for antimony in the case of 100-cm3 sample volumes. Therefore, it is suitable for determination of trace arsenic and antimony in natural waters.

Reaction of triarylbismuthines 1 with iodosylbenzene in dichloromethane under ultrasonic irradiation leads to the generation of triarylbismuthine oxides 2 as a bright yellow solution, in which activated alcohols are easily oxidized to carbonyl compounds, triphenylphosphine is converted into oxide and hydrazobenzene is rapidly dehydrogenated to azobenzene. Triphenylstibine 8 is similarly oxidized to give stibine oxide 9 , which lacks the corresponding oxidizing ability.

The synthesis of the common monodentate and bidentate stibines and bismuthines, and of multidentates containing one or more antimony or bismuth donor are briefly reviewed. The detailed coordination chemistries of SbH3, trialkyl- and triaryl-stibines and -bismuthines are described, followed by a treatment of distibine complexes and complexes of multidentates containing antimony (and rarely bismuth) in combination with other group 15 or 16 donors. The available X-ray structural data, antimony-121 Mossbauer results, and UV-visible data on these complexes are compiled. Throughout the article comparisons are drawn with complexes of lighter group 15 donor ligands and the considerable differences between stibine ligands and the more familiar phosphines and arsines are highlighted.

Arsine and stibine ligands stabilize bismuthenium cations and bismuthetidinium dications to give compounds containing As-Bi bonds and Sb-Bi bonds. The first enium-onium bonding environments in dications of the form [R'BiPnR(3)](2+) (Pn = As, Sb) contain the first definitive examples of carbenoid bismuth centers.

For the stibine isotopologue (SbH3)-Sb-121, we report improved theoretical calculations of the vibrational energies below 8000 cm- and simulations of the rovibrational spectrum in the 0-8000 cm(-1) region. The calculations are based on a refined ab initio potential energy surface and on a new dipole moment surface obtained at the coupled cluster CCSD(T) level. The theoretical results are compared with the available experimental data in order to validate the ab initio surfaces and the TROVE computational method [Yurchenko SN, Thiel vv, Jensen P.J mol Spectrosc 2007;245:126-40] for calculating rovibrational energies and simulating rovibrational spectra of arbitrary molecules in isolated electronic states. A number of predicted vibrational energies of (SbH3)-Sb-121 are provided in order to stimulate new experimental investigations of stibine. The localmode character of the vibrations in stibine is demonstrated through an analysis of the results in terms of local-mode theory

12 páginas, 6 figuras, 8 tablas, 1 esquema., The reaction of [AuCl(tht)] (tht = tetrahydrothiophene) with SbMesnPh3−n (n = 3 (1), 2 (2), 1 (3)) produces the 1:1 adducts [AuCl(SbMesnPh3−n)] (n = 3 (4), 2 (5), 1 (6)), with a Sb−Au−Cl environment, regardless of the molar ratio used (1:1 to 1:4). Addition of the same stibines to [Au(tht)2]ClO4 (molar ratio 1:1 to 1:4) results in isolation of the 1:2 adducts [Au(SbMesnPh3−n)2]ClO4 (n = 3 (7), 2 (10)), containing linear Sb−Au−Sb fragments, or the 1:3 adduct [Au(SbMesPh2)3]ClO4 (11), with a quasi trigonal planar AuSb3 core. The same 1:2 cations are produced when [Au(tht)2]CF3SO3 is reacted with 1 or following a rearrangement process when 4 is treated with AgSbF6, that is, [Au(SbMes3)2]X (X = CF3SO3 (8), SbF6 (9)). The compounds were characterized by spectroscopic methods, and the molecular structures of 2−4, 7, 8·2CDCl3, 9, and 11 were established by single-crystal X-ray diffraction. Theoretical calculations were carried out on model systems of type ER3 and [Au(ER3)n]+ (E = P or Sb; R = Ph or Mes; n = 2, 3, or 4) to gain insight into the bonding nature of SbR3 ligands in homoleptic gold-stibine adducts, in comparison with phosphine-gold(I) compounds. Steric effects govern the coordination of stibines with mesityl substituents. A preference for higher coordination numbers is observed for SbPh3 when compared with PPh3 and experimentally observed C−Sb−C and Sb−C structural distortions of stibines upon coordination are reproduced theoretically., Financial support from the Spanish MICINN (CTQ-2007-67273-C02-02), Ministry of Education and Research of Romania (Excellency Research Program, Research Project CEx-D11-16/2005; Project 19/2006) and National University Research Council (CNCSIS, Romania; Research Project Nos. A-709/2006, TD-397/2006 and ID- 2052/2009) is greatly appreciated.

The matrix isolation technique has been employed to isolate and characterize 1:1 molecular complexes of trimethylgallium with group VA bases. Several of these, including the (CH 3 ) 3 Ga-SbH 3 complex, are reported for the first time. All of the complexes were characterized by a red shift of the GaC 3 antisymmetric stretch and an activation of the GaC 3 symmetric stretch. In addition, numerous perturbed vibrational modes of the base subunit were observed

The synthesis, X-ray structure and spectroscopic characterization of new organo-rhodium(III) compounds is reported. From the reaction of RhCl3 with SbPh3 (Ph−C6H5, 1:3–4 molar ratio), in boiling ethanol, a mixture of [trans-RhCl2(Ph)(SbPh3)3] (1) and [mer-RhCl3(SbPh3)3] (2) was obtained. A previous hint on this reaction is given by R. Cini, G. Giorgi and E. Periccioli, Acta Crystallogr., Sect. C, 47 (1991) 716. The separation of 1 and 2 was carried out by recrystallizing the mixture from acetone: 1·(CH3)2CO precipitates first. 1 was separated from 2 also through chromatographic techniques (SiO2 column, CH2Cl2 eluent). High yield preparation of 1 was carried out on adding Ag(CF3SO3) to the suspension obtained by refluxing a mixture of RhCl3 and SbPh3 (Rh/ Sb/Ag molar ratio of 1:4:1). High yield synthesis of 2 was obtained by refluxing an ethanol mixture of RhCl3 and SbPh3 (1:3) in the presence of an excess of Cl−, or by refluxing a mixture of RhCl3 and SbPh3 (1:10) in ethanol solvent. Orange crystals of 1·0.45(CH3)2CO belong to the triclinic system, space group P 1 (No. 2) with a=12.686(2), b=14.906(2), c=15.523(3) A, α=107.73(2), β=95.10(2), γ=93.62(2)°, Z=2, Dc=1.60 g cm−3. The structure was refined to R=0.0594 and Rw=0.0651. The complex molecule consists of an octahedrally coordinated Rh(III) center linked to two trans Cl− ions, and to a Ph and to three SbPh3 ligands in the basal plane. A RhSb bond is much lengthened by a strong trans influence from the Ph ligand. 1 reacted with an excess of pyridine (Py) and 3,5-dimethylpyridine (3,5-lutidine, Lu) in refluxing methanol to produce [trans-RhCl2(Ph)(Py)3] (3) and [trans-RhCl2(Ph)(Lu)3] (4), respectively. 1 reacted also with boiling CH3CN to produce [RhCl2(Ph)- (CH3CN)(SbPh3)2] 3 reacted with an excess of 4-methylpyrimidine (Mp) in refluxing methanol to produce [trans- RhCl2(Ph)(Py)2(Mp)] (5). Yellow needles of 3 belong to the tetragonal system, space group I41/acd (No. 142), with a=15.660(2), c=17.044(2) A, Z=8, Dc=1.55 g cm−3. The structure was refined to R=0.0402 and Rw=0.0446. Yellow prisms of 4 belong to the tetragonal system, P4/nnc (No. 126), a=11.522(3), c=10.289(2) A, Z=2, Dc=1.39 g cm−3. The structure was refined to R=0.0579 and Rw=0.0601. Both 3 and 4 contain two Cl− ligands trans to each other, a Ph group and three Py or Lu molecules in the equatorial sites. Their 1H NMR spectra show large downfield shifts for the signals relevant to the Py or Lu ligand molecule trans to Ph. The 1H NMR spectrum of 5 shows that the two Py ligands are trans to each other and that Mp is coordinated through N(1), which occupies the position trans to Ph. The complex molecules of 3, 4 and 5 are stable in CHCl3 solution, at room temperature for periods of hours. The reaction of 2 with an excess of Py in refluxing methanol produced the well known complex [trans-RhCl2(Py)4]+.

In 1976, the Phillips Petroleum Company successfully demonstrated that the addition of certain organo-antimony compounds to a metal-contaminated heavy gas oil reduced the deleterious effects that metals such as Ni and V have on gasoline yields, coke, and hydrogen selectivities. Nickel has little effect on the activity of a fluidized cracking catalyst (FCC) but generates large amounts of gases, placing severe demands on capabilities of gas compressors. Marketed by Phillips Petroleum Company. Phil-Ad CA antimony organics have been shown to reduce by 50% gas formation due to metal contaminants, especially nickel. However, Sb, when introduced into a fluidized cracking unit, could reduce and form SbH[sub 3], stibine, that like arsine (AsH[sub 3]) is a highly toxic compound. Procedures for the safe usage of Sb in refining operations have been outlined; when used properly, Sb-containing passivating agents did not generate any detectable stibine. Recently, it has been reported that at microactivity test conditions, the additions of diluents (such as aluminas and layered magnesium silicates) capable of selectively sorbing metal contaminants from gas oils can form dual function cracking catalysts (DFCC) that retain most of their useful cracking activity even in the presence of as much as 1.0-1.5% V. It is themore » purpose of this paper to report the stability of Sb- and Sn-loaded alumina particles and the effects that the addition of metal passivation compounds such as Sb and Sn have on the performance of DFCC mixtures.« less

Under conditions which are non-optimum, such as low quartz tube atomizer temperatures, insufficient oxygen supply and excessively high analyte element concentrations, double peaks and a shift in time of the second peak may be observed in flow injection hydride generation atomic absorption spectrometry. These phenomena could be explained satisfactorily by a hydrogen radical depletion which results in the formation of mono- and di-hydrides of antimony and arsenic instead of atoms. These mono- and di-hydrides are thermally decomposed to the element and retained in the heated quartz tube and may be re-volatilized and atomized by reaction with hydrogen radicals. The phenomena described in this work strongly support the hydrogen radical mechanism of atomization of arsine and stibine in an externally heated quartz tube atomizer.

The two isotopic forms of stibine, 121 SbH 3 and 123 SbH 3 , have been spectroscopically studied with high resolution. Pure quadrupole resonances both in the ground and in the v 4 = 1 states have been observed using the infrared-radiofrequency double resonance technique in a CO 2 laser cavity. Characteristic hyperfine patterns resulting from direct l -type doubling transitions in the v 4 = 1 state have been measured by microwave spectroscopy. The hyperfine pattern in the ground state is reproduced following the standard treatment. Strong vibration-rotation interactions between the v 2 = 1 and v 4 = 1 states affect the observed spectrum in the v 4 = 1 state. A refined treatment of the vibration-rotation interactions between the hyperfine levels in this state was necessary in order to adequately analyze the experimental data. Quadrupole interaction parameters for a degenerate state of a symmetric-top molecule have been determined for the first time.

Medium-resolution Fourier transform infrared spectra of arsine, AsH 3 , and stibine, SbH 3 , have been measured in the wavenumber region 1800-8000 cm -1 . The strongest bands observed are due to stretching vibrations but also stretch/bend combination bands are observed. The observed stretching vibrational energy level patterns with close degeneracies are typical of molecules close to the local-mode limit. A three-parameter local-mode model which consists of coupled Morse oscillators is successfully used to explain the observed stretching vibrational spectra

The structures of (Me3Si)3Sb (1) and (Me3Si)3SbCr(CO)5 (2) have been determined by single-crystal X-ray diffraction. © 2000 Elsevier Science S.A. All rights reserved.

A novel method for the determination of antimony in environmental samples was developed with gas phase chemiluminescence detection following flow injection hydride generation and cryotrapping. The stibine, generated from samples by borohydride reduction of antimony using flow injection technique, was separated by using a new gas–liquid separator, dried with an ice-salt cryogenic bath and concentrated in a glass U-tube immersed in liquid nitrogen. Re-vaporization of stibine based on its boiling point was achieved by allowing the tube to warm at room temperature. A gas phase chemiluminescence signal was produced during the ozonation of the hydride in a reflective chamber. Under optimal conditions, the proposed method was characterized by a wide linear calibration range from 1.0 μg L−1 to 10.0 mg L−1 with a detection limit of 0.18 μg L−1 (n = 11). The relative standard deviation for 10.0 μg L−1 antimony was 3.56% (n = 11) and the sampling rate was 15 samples h−1. Blank signal was reduced by the purification of reagents and the interference from transition metal ions was eliminated by the addition of l -cysteine into samples. The method was applied to the determination of antimony in environmental samples with satisfactory results.

A high‐resolution Fourier‐transform infrared spectrum, resolution about 0.006 cm−1, of the first stretching overtone band system of stibine has been measured and rotationally analyzed in detail up to J’=22 for both 121SbH3 and 123SbH3 isotopic species. The rotational levels of the A1 and E vibrational states have been analyzed simultaneously by including vibration–rotation coupling terms in the Hamiltonian for the two isotopic species. The A1/E vibrational energy‐level separation has been found to be 0.0727(8) cm−1 for 121SbH3 and 0.0763(8) cm−1 for 123SbH3 with the A1 state being higher in energy in both cases. Fits including 1445 transitions with the standard deviation of 0.0024 cm−1 for 121SbH3 and 1322 transitions with the standard deviation of 0.0022 cm−1 for 123SbH3 have been obtained by optimizing altogether 33 upper‐state parameters in both cases. A simple local‐mode model is shown to account very well for the vibrational dependence of the rotational constants and the coefficients of vibrationally...

Good routes have been developed to the mono- and bis-substituted derivatives [Os 6 (CO) 17 L] (L = P(OMe) 3 , PEt 3 , PPh 2 Me, PPh 3 , AsPh 3 or SbPh 3 ) and [Os 6 (CO) 16 L′ 2 ] (L′ = PPh 3 , PPh 2 Me), which have structures based on the same bicapped tetrahedral OS 6 -unit established for [Os 6 (CO) 18 ]. The [Os 6 (CO) 16 L′ 2 ] compounds apparently exist in more than one isomeric form and small amounts of the tris-substituted derivatives [Os 6 (CO) 15 L′ 3 ] are also observed. The mono-substituted hexaosmium cluster [Os 6 (CO) 17 L] undergoes reaction with Me 3 NO in CH 2 Cl 2 to yield the previously unknown hydridohexaosmium anion [HOs 6 (CO) 16 L] − which on reaction with HBF 4 ·Et 2 O first gives the neutral hexaosmium dihydride [H 2 Os 6 (CO) 16 L] and then the cation [H 3 Os 6 (CO) 16 L] + . The bis-substituted hexaosmium cluster [Os 6 (CO) 16 L 2 ] reacts similarly with Me 3 NO/CH 2 Cl 2 to give the hydrido-anion [HOs 6 (CO) 16 L 2 ] − .