| 1. |
- Bauschlicher, C.W., et al.
(författare)
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A further study of the products of scandium and dioxygen reactions
- 1999
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Ingår i: Journal of Physical Chemistry A. - 1089-5639 .- 1520-5215. ; 103:28, s. 5463-5467
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Tidskriftsartikel (refereegranskat)abstract
- The products of the reaction of Sc and dioxygen have been reinvestigated. By adding the electron-trapping molecule CCl4 additional information about the IR spectra has been obtained, as well as the observation of new bands. New ab initio calculations are also performed on possible products of the Sc plus O-2 reaction. The previously observed band at 722.5 cm(-1) is assigned as the b(2) mode of ScO2-. Bands arising from ScO+, Sc(O-2)(+), and(O-2)ScO are also assigned. We are still unable to assign any bands to OScO. The problems associated with the computational study of ScO2 are discussed.
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| 2. |
- Snis, Anders, et al.
(författare)
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Characterizations of (NO)(3)- and N3O2- molecular anions
- 1999
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Ingår i: Chemical Physics Letters. - 0009-2614. ; 305:3-4, s. 285-292
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Tidskriftsartikel (refereegranskat)abstract
- Isomers of (NO)3− are characterized by means of B3LYP density functional theory and the wavefunction-based CASPT2 method. Stabilities, vertical electron detachment energies (VDEs), vertical electron excitation energies (VEEs), and vibration frequencies are determined. Experimental isotope shifts in the IR spectrum of (NO)3− and theory were previously employed to determine the structure of an N–N–N connected anion. Further support for this assignment is obtained in the present study by comparing experimental and theoretical VDEs and VEEs. A parallel analysis of a w-shaped N3O2− molecular anion along the above lines is performed for reference, as a comprehensive understanding of the two systems is sought.
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| 3. |
- Nilsson, Mattias, et al.
(författare)
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Synthesis, structural characterisation and magnetic properties of Gd14W4O33-xNy(0<=x<=17+/-2, 0<=y<=9+/-2), a new fluorite-related oxynitride
- 1996
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Ingår i: Journal of Alloys and Compounds. - : Elsevier BV. - 0925-8388 .- 1873-4669. ; 240:1-2, s. 60-69
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Tidskriftsartikel (refereegranskat)abstract
- A series of crystalline Gd-W oxides, with Gd:W ratios spanning the values 0.1-3.5, has been prepared and treated with a flow of NH3(g) in the temperature range 700-1100 degrees C. Besides the previously reported formation of GdWO3N and Gd2WO3N2, the following new results were obtained: (i) cubic Gd0.1WO3 upon ammonolysis forms an (oxy)nitride Gd0.1W(O,N)(y) with an f.c.c. lattice; (ii) the previously described Gd2WO3N2 exhibits a solid solubility range Gd3-xW1+x(O,N)(y) with, approximately, 0 less than or equal to x less than or equal to 1; (iii) ammonolysis of Gd14W4O33 yields an oxynitride, the composition of which varies with the synthesis temperature according to Gd14W4O33-xNy(O less than or equal to x less than or equal to 17+/-2, 0 less than or equal to y less than or equal to 9+/-2). All strong diffraction lines, including those of the pure oxide (x = y = 0), can be indexed with a body-centred monoclinic unit cell derived from that of fluorite. For Gd14W4O33 the cell 3 parameters are a = 5.3592(11), b = 3.7295(7), c = 3.8636(8) Angstrom, beta = 92.170(2)degrees and V = 77.17 Angstrom(3). However, strong superstructure reflections in the electron diffraction patterns indicate that the true unit cell is considerably larger. A partial structure determination of Gd14W4O33-xNy has been carried out by the Rietveld method. Magnetic susceptibility measurements in the temperature interval 15-300 K show a Curie-Weiss law behaviour for Gd14W4O33-xNy, with mu(eff) = 8.08+/-0.06 Bohr magntons per Gd3+ and theta = -12.4+/-1.1 K for all compositions.
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| 4. |
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| 5. |
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| 6. |
- Foreman, Mark, 1973, et al.
(författare)
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PREPARATION AND X-RAY STRUCTURE OF A NEW ORGANO-P-O-S HETEROCYCLE
- 1995
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Ingår i: Chemical Communications. ; :21, s. 2217-2218
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Tidskriftsartikel (refereegranskat)abstract
- Reaction of 1,3-epithio-1 lambda(5),3 lambda(5)-naphtho[1,8-cd][1,2,6]thiadiphohosphinine-1,3-dithione 5 with 3,5-di-tert-butylcatechol gives 3,5-di-tert-butyl-1,8-epithio-1 lambda(5),8 lambda(5)-naphtho[1,8 -cd][1,7,2,6]benzodioxadiphosphonine-1,8-dithione 7 which, from X-ray studies, contains fused C3P2S and C2O2P2S rings.
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| 7. |
- Foreman, Mark, 1973, et al.
(författare)
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The preparation of a solubilized form of Lawessons reagent and its thionation reactions
- 1999
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Ingår i: Heteroatom Chemistry. - 1098-1071 .- 1042-7163. ; 10:7, s. 651-657
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Tidskriftsartikel (refereegranskat)abstract
- 2-tert-Butylanisole and P4S10 react together to give 2,4-bis (3-tbutyl-4-methoxyphenyl) 1,3, 2, 4-dithiadiphosphetane 2, 4-disulfide (LR*) which was characterized by X-ray crystallography. Comparative thionation reactions of LR* and a range of P-S compounds were investigated. If was found that LR* in many cases, gives better yields of thionated complexes than Lawessons Reagent when the reactions are performed at room temperature. (C) 1999 John Wiley & Sons, Inc.
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| 8. |
- Istomin, S Y, et al.
(författare)
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Synthesis and characterization of the reduced niobates CaLnNb2O7, Ln = La-Pr, Sm, Gd-Lu, with the pyrochlore-type structure
- 1998
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Ingår i: Materials research bulletin. - 0025-5408 .- 1873-4227. ; 33, s. 1251-1256
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Tidskriftsartikel (refereegranskat)abstract
- New reduced niobates, CaLnNb2O7, Ln = La-Pr, Sm, Gd-Lu, with the pyrochlore-type structure were synthesized in sealed Nb ampoules at 1350–1500°C for 6–10 h. The prepared compounds were characterized by powder X-ray diffraction, energy dispersive X-ray analysis, and thermogravimetric analysis. The magnetic measurements showed that all of the samples except the La, Sm, and Lu compounds exhibited Curie-Weiss behavior. The compounds were found to be electrically insulating.
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| 9. |
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| 10. |
- Snis, Anders, et al.
(författare)
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N2O2, N2O2- and N2O22-: structures, energetics and N-N bonding
- 1997
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Ingår i: Chemical Physics. - 0301-0104. ; 221:1-2, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- The density functional theory and the ab initio quantum chemistry methods, Becke3LYP and CASPT2, have been employed to determine structures and energetics of neutral and anionic N2O2 species. When going from a neutral NO dimer to an anionic species the N---N bond lengths decrease drastically and the corresponding N---N frequencies increase. The relative stabilities of the different N2O2− isomers suggest an ONNO structure in a Trans configuration to be the most stable mono valent anion. The formation energies of 1.4–1.7 eV relative to the NO + NO− asymptote are in agreement with experiments. Excitation energies are determined and specific formation channels for three N2O2− isomers are discussed. The hyponitrite ion, N2O22−, is also studied. Its total energy is 2.7–2.8 eV above the total energy of two NO−. In order to connect to an experimental study of NO adsorption on MgO the ability of two NO molecules to form a complex with Mg and Mg+ is investigated.
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