638 research outputs found
Sympathetic cooling in a mixture of diamagnetic and paramagnetic atoms
We have experimentally realized a hybrid trap for ultracold paramagnetic
rubidium and diamagnetic ytterbium atoms by combining a bichromatic optical
dipole trap for ytterbium with a Ioffe-Pritchard-type magnetic trap for
rubidium. In this hybrid trap, sympathetic cooling of five different ytterbium
isotopes through elastic collisions with rubidium was achieved. A strong
dependence of the interspecies collisional cross section on the mass of the
ytterbium isotope was observed.Comment: 4 pages, 4 figure
Production of ultracold heteronuclear YbRb* molecules by photoassociation
We have produced ultracold heteronuclear YbRb molecules in a combined
magneto-optical trap by photoassociation. The formation of electronically
excited molecules close to the dissociation limit was observed by trap loss
spectroscopy in mixtures of Rb with Yb and Yb. The
molecules could be prepared in a series of vibrational levels with resolved
rotational structure, allowing for an experimental determination of the
long-range potential in the electronically excited state
Synthesis, Crystal Structure, and Spectral Characteristics of N-(tert-Butyl) aminomethanesulfonic Acid
A new method of the synthesis of N-(tert-butyl)aminomethanesulfonic acid in the system SO2â(CH3)3CNH2âCH2OâH2O was developed. The target compound [(CH3)3ĐĄ]NHCH2SO3H was characterized by means of X-ray diffraction analysis, IR spectroscopy, and mass spectrometry
Cs2Bi(PO4)(WO4)
Dicaesium bisÂmuth(III) phosphate(V) tungstate(VI), Cs2Bi(PO4)(WO4), has been synthesized during complex investigation in a molten pseudo-quaternary Cs2OâBi2O3âP2O5âWO3 system. It is isotypic with K2Bi(PO4)(WO4). The three-dimensional framework is built up from [Bi(PO4)(WO4)] nets, which are organized by adhesion of [BiPO4] layers and [WO4] tetraÂhedra above and below of those layers. The interÂstitial space is occupied by Cs atoms. Bi, W and P atoms lie on crystallographic twofold axes
Synthesis, Crystal Structure, Vibrational Spectra, and Thermochemical Transformations of Tris(hydroxymethyl)aminomethane
AbstractâA practically promising compound, tris(hydroxymethyl)aminomethane sulfate ((TRISH)2SO4,
C8H24N2O10S) was synthesized and studied by a set of experimental methods (elemental analysis, IR and
Raman spectroscopy, mass spectrometry, thermogravimetry)
Products of Interaction between Sulfur(IV) Oxide and Aqueous Solutions of Hexamethylendiamine and tertButylamine: The Crystal Structure of Hexamethylenediammonium Sulfate Dihydrate
The possibility of mild SO2 oxidation in sulfur(IV) oxideâalkylamineâwaterâoxygen systems is demonstrated to yield onium sulfates
Synthesis and Structure of Aminoguanidinium Sulfite Monohydrate
AbstractâThe reaction between sulfur(IV) oxide and an aqueous suspension of aminoguanidinium hydro
carbonate yields (CN4H7)2SO3 â
H2O, an âoniumâ sulfite, which has been characterized by Xray diffraction
and IR spectroscopy and mass spectrometry. The structure of the salt is stabilized by numerous Hbonds, such
as NHâ
â
â
O, OHâ
â
â
O, and NHâ
â
â
N. The incorporation of pyramidal ions into the network of Hbonds is
accompanied by the lowering of their symmetry in comparison with C3v, thus complicating the IR spectra of
the salt in the region where the vibrations of the anion appear
Interaction Products in the System Sulfur Dioxideâ2,2âČ-BipyridineâWater. Van der Waals Clathrates
Crystallization of 2,2âČ-bipyridine from aqueous solution containing sulfur(IV) oxide afforded clathrates with the composition (bipy)k·(SO2)m·(H2O)n. X-Ray amorphous guest SO2 molecules occupy voids in the crystal lattice of 2,2âČ-bipyridine without distortion of its structure. The isolated compounds were
characterized by elemental analyses, X-ray diffraction data, and IR, NMR, and mass spectra
Onium Salts of Sulfur-Containing Oxyanions Resulting from Reaction of Sulfur(IV) Oxide with Aqueous Solutions of 1,2-Diamines and Morpholine
Reaction products have been isolated from SO2âLâH2OâĐ2 systems (L = ethylenediamine,
N,N,N',N'-tetramethylethylenediamine, piperazine, and morpholine) as onium salts
[H3NCH2CH2NH3]SO4, [(CH3)2NHCH2CH2NH(CH3)2]SO4, [(CH3)2NHCH2CH2NH(CH3)2]S2O6 â
H2O, [C4H8N2H4]SO3 â
H2O, [C4H8N2H4]S2O6, [C4H8N2H4]SO4 â
H2O, [O(C2H4)2NH2]2SO4 â
H2O. The
prepared compounds have been characterized by X-ray diffraction analysis, X-ray powder diffraction, IR and
mass spectroscopy
Synthesis and Structure of N(Hydroxyethyl)ethylenediammonium Sulfite Monohydrate
A reaction between sulfur(IV) oxide and aqueous N(2hydroxyethyl)ethylenediamine yields
onium sulfite of composition (HOCH2CH2NH2CH2CH2NH3)SO3 â
H2O, which has been characterized by
Xray diffraction, IR spectroscopy, and mass spectrometry. The threedimensional structure of the salt is stabilized by numerous hydrogen bonds, such as NHâ
â
â
O and OHâ
â
â
O
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