The Experts below are selected from a list of 59187 Experts worldwide ranked by ideXlab platform
S. Radice - One of the best experts on this subject based on the ideXlab platform.
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Perfluoropoly-ether/peroxide compounds: spectroscopic studies and Quantum Chemical Calculations
Journal of Fluorine Chemistry, 2004Co-Authors: S. Radice, Paolo Toniolo, Emma Barchiesi, P.a. Guarda, Matteo Tommasini, Chiara CastiglioniAbstract:Abstract Perfluoropolyethers (PFPEs) are a class of high performance materials used in a wide range of applications (refrigeration, lubrication, semiconductor industry, etc.). PFPEs containing peroxidic units are intermediate materials for the preparation of commercial end products. In this work we study the spectroscopic properties of ether and peroxides linkages in this class of compounds; nuclear magnetic resonance (NMR) spectra are discussed, FT-Raman data presented. Quantum Chemical Calculations on model molecules were used as a tool for the interpretation of the Raman experimental data and physical–Chemical properties.
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Vibrational spectra and Quantum Chemical Calculations of some polyfluoroethers
Journal of Fluorine Chemistry, 1998Co-Authors: S. Radice, M. Causà, G. MarchionniAbstract:Abstract Vibrational spectroscopy and Density Functional Theory (DFT) Quantum Chemical Calculations, have been used to investigate structure and Chemical properties of some fluorinated ethers. A good agreement between experimental and theoretical results has been obtained. Interesting conformational behaviour has been observed and interpreted for C-H bonds in difluoromethyl end groups. These effects help in understanding the Chemical behaviour of these compounds, since C-H equilibrium bond length and bond dissociation energy (BDE) can be correlated with Vibrational properties.
Chiara Castiglioni - One of the best experts on this subject based on the ideXlab platform.
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Perfluoropoly-ether/peroxide compounds: spectroscopic studies and Quantum Chemical Calculations
Journal of Fluorine Chemistry, 2004Co-Authors: S. Radice, Paolo Toniolo, Emma Barchiesi, P.a. Guarda, Matteo Tommasini, Chiara CastiglioniAbstract:Abstract Perfluoropolyethers (PFPEs) are a class of high performance materials used in a wide range of applications (refrigeration, lubrication, semiconductor industry, etc.). PFPEs containing peroxidic units are intermediate materials for the preparation of commercial end products. In this work we study the spectroscopic properties of ether and peroxides linkages in this class of compounds; nuclear magnetic resonance (NMR) spectra are discussed, FT-Raman data presented. Quantum Chemical Calculations on model molecules were used as a tool for the interpretation of the Raman experimental data and physical–Chemical properties.
David W. H. Rankin - One of the best experts on this subject based on the ideXlab platform.
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molecular structures of free quinuclidine and its adducts with metal trihydrides mh3 m b al or ga studied by gas phase electron diffraction x ray diffraction and Quantum Chemical Calculations
Dalton Transactions, 2007Co-Authors: Derek A. Wann, Frank Blockhuys, Christian Van Alsenoy, Heather E. Robertson, Hans-joerg Himmel, Christina Y. Tang, Andrew R. Cowley, Anthony J. Downs, David W. H. RankinAbstract:The structure of quinuclidine, HC(CH2CH2)3N, has been re-investigated by Quantum Chemical Calculations and by gas-phase electron diffraction (GED). The GED data, together with published rotational constants, have been analysed using the SARACEN method to determine the most reliable structure (rh1) for the gaseous molecule. The structures of two adducts of quinuclidine with group 13 trihydride molecules, MH3 (M = B, Al), have also been determined by GED and Quantum Chemical Calculations. The effect of the coordination of these hydrides to the quinuclidine nitrogen atom has been investigated, and the structural changes and energetics of adduct formation are discussed. We also present the crystal structure of quinuclidine borane.
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Molecular structures of free quinuclidine and its adducts with metal trihydrides, MH3 (M = B, Al or Ga), studied by gas-phase electron diffraction, X-ray diffraction and Quantum Chemical Calculations
Dalton transactions (Cambridge England : 2003), 2007Co-Authors: Derek A. Wann, Frank Blockhuys, Christian Van Alsenoy, Heather E. Robertson, Hans-joerg Himmel, Christina Y. Tang, Andrew R. Cowley, Anthony J. Downs, David W. H. RankinAbstract:The structure of quinuclidine, HC(CH2CH2)3N, has been re-investigated by Quantum Chemical Calculations and by gas-phase electron diffraction (GED). The GED data, together with published rotational constants, have been analysed using the SARACEN method to determine the most reliable structure (rh1) for the gaseous molecule. The structures of two adducts of quinuclidine with group 13 trihydride molecules, MH3 (M = B, Al), have also been determined by GED and Quantum Chemical Calculations. The effect of the coordination of these hydrides to the quinuclidine nitrogen atom has been investigated, and the structural changes and energetics of adduct formation are discussed. We also present the crystal structure of quinuclidine borane.
Horst Förster - One of the best experts on this subject based on the ideXlab platform.
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Quantum Chemical Calculations on cationic positions and adsorption complexes in A-type zeolite
Studies in Surface Science and Catalysis, 1995Co-Authors: Gy. Tasi, Imre Kiricsi, I. Farkas, L. Nyerges, Horst FörsterAbstract:Semiempirical Quantum Chemical Calculations (MNDO, AM1 and PM3) have beenperformed for determining the possible positions of exchangeable cations and geometries of sorption complexes of cyclopropane and propene in zeolite A.
Jürgen Gauss - One of the best experts on this subject based on the ideXlab platform.
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silicon oxysulfide osis rotational spectrum Quantum Chemical Calculations and equilibrium structure
Journal of Physical Chemistry Letters, 2011Co-Authors: S Thorwirth, Jürgen Gauss, Leonie Anna Muck, Filippo Tamassia, Valerio Lattanzi, M C MccarthyAbstract:Silicon oxysulfide, OSiS, and seven of its minor isotopic species have been characterized for the first time in the gas phase at high spectral resolution by means of Fourier transform microwave spectroscopy. The equilibrium structure of OSiS has been determined from the experimental data using calculated vibration-rotation interaction constants. The structural parameters (rO-Si = 1.5064 A and rSi-S = 1.9133 A) are in very good agreement with values from high-level Quantum Chemical Calculations using coupled-cluster techniques together with sophisticated additivity and extrapolation schemes. The bond distances in OSiS are very short in comparison with those in SiO and SiS. This unexpected finding is explained by the partial charges calculated for OSiS via a natural population analysis. The results suggest that electrostatic effects rather than multiple bonding are the key factors in determining bonding in this triatomic molecule. The data presented provide the spectroscopic information needed for radio astronomical searches for OSiS.
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The hyperfine structure in the rotational spectra of D2O: Lamb-dip measurements and Quantum-Chemical Calculations
Molecular Physics, 2010Co-Authors: Gabriele Cazzoli, Luca Dore, Cristina Puzzarini, Jürgen GaussAbstract:Thirteen rotational transitions of the doubly deuterated isotopic species of water, D216O, have been recorded in the millimeter- and submillimeter-wave region. The Lamb-dip technique has been used to resolve the hyperfine structure due to deuterium quadrupole coupling, due to spin-rotation as well as dipolar spin-spin interactions, thus enabling the determination of the corresponding hyperfine parameters to a good accuracy. The experimental investigation has been assisted by high-level Quantum-Chemical Calculations of the hyperfine parameters.
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Characterization of cis- and trans-HSSOH via rotational spectroscopy and Quantum-Chemical Calculations.
Inorganic chemistry, 2009Co-Authors: Monika Koerber, Oliver Baum, Thomas F. Giesen, Stephan Schlemmer, Josef Hahn, Jürgen GaussAbstract:Assisted by high-level Quantum-Chemical Calculations, the cis and trans conformers of HSSOH have been unambiguously identified among the products of the flash-vacuum pyrolysis of tert-butylthiosulfinic acid S-tert-butylester by using rotational spectroscopy.
