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The ground-state rotational spectra of five isotopomers (H2S...(35)Cl2, H2S...(35)Cl(37)Cl, H2S...(37)Cl(35Cl), HDS...(35)Cl2 and D2S...(35)Cl2) of a complex formed by hydrogen sulfide and chlorine have been observed with a pulsed-nozzle, Fourier-transform microwave spectrometer.The reaction of H2S and Cl2 was precluded by employing a fast-mixing nozzle.The rotational constant 1/2(Bo + Co), the centrifugal distortion constant DJ and the Cl-nuclear quadrupole coupling constants χaa(Cli) and χaa(Clo) (i = inner Cl atom, o = outer Cl atom) were determined in each case.The rotational constants were interpreted, under the assumption of unperturbed monomer geometries, to establish that H2S...Cl2 has a geometry in which the SClCl nuclei are collinear or almost collinear, with the Cl2 subunit nearly perpendicular to the plane of the H2S nuclei.The observed angular geometry is rationalised in terms of a set of rules previously used to discuss hydrogen-bonded complexes B...HX.The strength of the interaction, as measured by the force constant k? (determined from DJ), and the electric charge redistribution within Cl2 on formation of H2S...Cl2 aa(Clx)> both indicate that the complex is of the weak, outer type described by Mulliken.A comparison of the properties of H2S...Cl2 and H2S...HCl reveals that the complexes are similar in several respects and explanations for these similarities are given in terms of the electric charge distributions of Cl2 and HCl.In particular, the reason why the angular geometries of both can be predicted by some electrostatically based rules is discussed.

The univariant (1112g) saturation vapor pressure of liquid deuterium oxide (phase I1) with liquid deuterium sulfide (phase I2) in equilibrium with a gas phase (g) has been measured in a stirred titanium reaction vessel at 19 temperatures from 33.003 to 18.905°C and at total pressures from 2.4500 to 1.7428 MPa. The univariant (hl1g) saturation vapor pressure of deuterium sulfide D-hydrate (phase h) in equilibrium with liquid deuterium oxide and a gas phase has been measured at 58 temperatures from 30.666 to 2.798°C and at pressures from 2.2959 to 0.11629 MPa. The maximum temperature for deuterium sulfide D-hydrate with a gas phase, the invariant quadruple point Q(h1112g), has been determined from the cut of the (h11g) and the (l112g) curves at temperature 30.770°C with standard error 0.0043°C and at pressure 2.3263 MPa with standard error 0.00018 MPa. The univariant (s111g) equilibrium of D-ice (phase s1) with liquid deuterium oxide and a gas phase containing deuterium sulfide has been measured at 11 temperatures from 3.8061 to 3.4540°C and at pressures between 0.00242 and 0.10542 MPa. The lowest temperature for stability of deuterium sulfide D-hydrate with liquid deuterium oxide, the invariant quadruple point Q(hs111g), has been determined directly at 3.3917°C with standard error 0.0009°C and at pressure 0.12364 MPa with standard error 0.000011 MPa. This quadruple point Q(hs111g) has also been defined by the cut of the (hl1g) and the (s111g) curves at temperature 3.3912°C with standard error 0.0006°C and at pressure 0.12363 MPa with standard error 0.000002 MPa. The deuterium sulfide - deuterium oxide gas mixture, represented by a Redlich-Kwong equation of state, has been used to evaluate the fugacities and compositions of the gaseous and liquid deuterium oxide phases for all equilibria. Raoult's law using fugacities has been used to evaluate the saturation mole fraction of deuterium oxide in liquid deuterium sulfide and the Henry's law constant for deuterium oxide solubility in liquid deuterium sulfide between 33.003 and 18.905°C. Data for the (I112g) and (s111g) equilibria have been accurately represented by simple two-parameter equations. Data for the (hl1g) equilibrium have required a model with seven significant parameters for proper representation between 30.666 and 2.798°C.

Structure and dynamics of CsHS and CsDS compounds were studied using neutron diffraction, solid state 1-nuclear magnetic resonance, and calorimetric investigations in a wide temperature range. Large-amplitude liberations of DS- were

The reaction between H2S and ClF was precluded and H2S...ClF isolated bya coaxial supersonic expansion of the gaseous components into the Fabry -Perot cavity of a pulsed-nozzle, Fourier-transform microwave spectrometer. The ground-state rotational spectra of seven isotopomers of H2S...ClF were analysed and gave in each case the spectroscopic constants 1/2(B(0)+C(0)), D(J), χ(aa) (Cl) and M(bb) (Cl). Interpretation of these constants revealed the complex to have a geometry of C(s) symmetry with the S...Cl-F nuclei collinear in the order shown, with the angle 180°-φ=84.2(4)° between the C(2) axis of H2S and the S...Cl-F axis, and with r(S...Cl)=2.857(3)?.

The structure of NH3*H2S has been determined from microwave and radiofrequency spectroscopy of this complex and its deuterated isotopomers, using molecular beam electric resonance techniques.Rotational constants, electric dipole moments and nitrogen quadrupole coupling constants were obtained from the spectra.The molecule was found to have a linear, hydrogen bonded structure with the ammonia as the proton acceptor.The NS distance is 3.639 Angstroem, the root-mean-square angular deviation of the NH3 axis from the N-S axis is 24.6 deg and the H2S C2 axis is 40.5 deg from the N-S axis.Although the molecule is an asymmetric rotor, first-order Stark effects were observed for K = 1 rotational levels.These Stark effects are caused by torsional oscillations which are essentially ammonia monomer free internal rotation.Similar effects were observed for NH3*H2O and are reported here.

The technique of cavity ring-down spectroscopy has been used to investigate predissociation in the A 2Σ+ state of the SH and SD radicals. Spectra were recorded of the A-X (1,0) band of SH and the (1,0), (2,0) bands of SD. Linewidth measurements of transitions to individual rovibrational levels of the A state revealed increasing predissociation rates with vibrational and rotational quantum number. These and all other available data have been reproduced, quantitatively, by Fermi Golden Rule calculations employing the best (experimentally determined) analytic potential for the A state and ab initio repulsive potentials and spin-orbit coupling matrix elements.

The technique of H(D) atom photofragment translational spectroscopy has been applied to the photodissociation of H2S(D2S) following excitation at a number of wavelengths in its first absorption continuum.The respective bond dissociation energies were determined as D0(H-SH) = 3.90 +/- 0.03 eV and D0(D-SD) = 4.00 +/- 0.02 eV.The measured vibrational energy disposal in the partner ground state SH(SD) fragments and the product angular distributions support and extend the earlier results of van Veen et al. , while the deduced rotational andspin-orbit state population distributions in these fragments appear to be generally consistent with the recent measurements of Weiner et al. .We present a schematic adiabatic potential energy surface for the dissociative 1A'' excited state via which it is possibe to rationalize virtually all existing dynamical measurements relating to this fragmentation process.

Merged jet copyrolysis of mixtures of Ar/B2H6 and Ar/H2S followed by trapping in a cryogenic matrix has led to the formation, isolation, and characterization of mercaptoborane, H2BSH.Eight of the nine fundamentals of this molecule were observed, including the boron-sulfur stretching mode at 804 cm-1 ((11)B).Local density functional and normal-coordinate calculations were carried out to assist in assigning the observed fundamentals.The position of B-S stretching mode, compared to a range of known compounds, suggests single bond character for the B-S bond.Additional products were observed, including HBS, and suggests further reaction of H2BSH at high temperatures.A mechanism for the reaction is proposed.

The degradation of SF6 and SF5 organyls by S-F and S-C bond-activation reactions at [{Rh(μ-H)(dippp)}2] under mild conditions is reported. Fluorido and thiolato species were identified as products or intermediates, and were characterized by X-ray diffraction analysis and multinuclear NMR spectroscopy. An unprecedented cyclic process for the conversion of the potent greenhouse gas SF6 into H2S was developed. Activation of the stable greenhouse gas SF6: The rhodium hydrido complex [{Rh(μ-H)(dippp)}2] effected defluorination at the sulfur atom of SF6 and organic SF5 compounds under mild conditions. The reduction of SF6 in the presence of HSiEt3 led exclusively to the thiolato complex [Rh2(μ-H)(μ-SSiEt 3)(dippp)2] and FSiEt3 (see Scheme). A cyclic process was developed for the conversion of SF6 into H2S.

The present invention relates to a non-radioactive, heavy-atom isotopologue of Compound 1 containing one or more deuterium in place of a hydrogen covalently bound to carbon. The Compound 1 isotopologues of the invention are inhibitors of norepinephrine up

The Lyman-α dissociation of H2S and its deuterated isotopomer, D2S, were re-evaluated using the technique of H(D) atom PTS. Kinetic energy resolved recoil anisotropy (β) parameters, β(TKER), were elucidated. Experimental studies were

Variable-time neutralization-reionization mass spectrometry is used to generate isotopomers of metastable hydrosulfonium radicals, H3S(.), of lifetimes ranging between 0.2 and 2.8 μs.The fractions of metastable H3(32)S(.), H3(34)S(.), D3(32)S(.), D3(34)S(

The deuteron-proton liquid phase isotopic disproportionation constant in hydrogen sulphide, K1, defined for the equilibrium has been measured at 25.7 deg C.The value of K1 was 3.99+/-0.11, based upon direct measurements of the concentrations of the three molecular species H2S, HDS, and D2S by 1H and 2H nuclear magnetic resonance spectroscopy (nmr) of carefully purified samples.This compares with the theoretical vapour phase isotopic distribution constant, Kv = 3.92, calculated from ideal gas vapour phase isotopic partition function ratios (1, 2).

Deuterium, introduced as D2S to a molybdenum disulphide catalyst, has been found to exchange with gas-phase hydrogen and to be incorporated into hydrocarbon products when buta-1,3-diene is hydrogenated on the catalyst; evidence is presented for the participation of hydrogen present on the surface as SH groups.

Rate constants have been measured for reactions of the type AD2+ + MH --> MD + ADH+, where AD2+ is CD3CND+, CD3CDOD+, (CD3COCD3)D+, or (C2D5)2OD+ and the MH molecules are alcohols, acids, mercaptanes, H2S, AsH3, PH3, or aromatic molecules.Rate constants are also presented for the reactions ArHD+ + D2O --> ArDD+ + HDO, where ArHD+ is a deuteronated aromatic molecule and ArDD+ is the same species with a D atom incorporated on the ring.In all but two cases, the competing deuteron transfer is sufficiently endothermic that it cannot be observed under the conditions of the ICR experiments at 320 - 420 K.The efficiencies of the isotope exchange reactions are interpreted in terms of estimated potential surface cross sections for the reactions AD2+ + MH --> 2+*MH> --> +> --> +*MD> --> ADH+ + MD.When the formation of the +> complex is estimated to be thermoneutral or slightly endothermic, the isotope exchange process is inefficient (probability of a reactive collision 2+*MH> --> +> is exothermic.For most of the systems, trends in reaction efficiency appear to be related to factors such as dipole moments of reactant species (or for aromatic compounds, the electron-donating or -withdrawing properties of ring substituents) which influence the relative orientation of the two reactant species in the complex.