Untersuchungen über die magnetische Kernresonanz von Alkalikernen in wäßriger Lösung

1968 ◽  
Vol 23 (8) ◽  
pp. 1202-1209 ◽  
Author(s):  
O. Lutz
Keyword(s):  
Aqueous Solutions ◽  
Optical Pumping ◽  
Magnetic Moments ◽  
Water Molecules ◽  
Nuclear Magnetic Moments ◽  
Lanthanide Elements ◽  
Free Ion ◽  
Shielding Constants ◽  
The Difference ◽  
Nmr Signals

The NMR signals of the nuclei 2H, 6Li, 7Li, 23Na, 87Rb and 133Cs have been investigated in aqueous solutions. The ratios of the Larmor-frequencies of these alkali nuclei relative to 2H have been measured with high accuracy. Because the Larmor-frequencies depend on the concentration of the aqueous solutions, an extrapolatiton to vanishing concentration was made. From these ratios of Larmor-frequencies, a magnetic moment for the alkali nuclei has been derived and has been compared with the available nuclear magnetic moments from atomic beam or optical pumping experiments. The difference in the magnetic moments results from the shielding of the alkali nuclei by the water molecules around the ions. The shielding constants are: σ (Rb+) = — (2.0 ± 0.2) ·10-4 and σ (Cs+) = — (3.4 ± 0.1) · 10-4 relative to the free ion.The shift of the 133Cs NMR line as a function of the concentration of aqueous solutions of Cssalts is given in detail. The influence of the chlorides of some elements in the iron group and of some lanthanide elements on the position of the 133Cs NMR line is shown.

Atomic Reference Scale for Chemical Shifts of Rubidium

1972 ◽  
Vol 27 (11) ◽  
pp. 1577-1581 ◽  
Author(s):  
O. Lutz ◽  
A. Nolle
Keyword(s):  
Infinite Dilution ◽  
Optical Pumping ◽  
Chemical Shifts ◽  
High Accuracy ◽  
Water Molecules ◽  
Solid States ◽  
Reference Scale ◽  
Shielding Constants ◽  
The Difference ◽  
Nmr Signals

Abstract With a multi-nuclei Fourier transform NMR spectrometer the ratio of the Larmor frequencies of 85Rb and 2H in a solution of RbCl in D2O has been measured with high accuracy. The concentration dependence of the 85Rb NMR signals has been determined in solutions of rubidium salts in H2O and D2O. Using this dependence, the ratio of the Larmor frequencies of the 85 Rb nuclei for infinite dilution relative to 2 H in pure D20 is given. From this a gI-factor for 85Rb has been derived and has been compared with the gI-factor of an optical pumping experiment. The difference in the gI-factors results from the shielding of the rubidium nuclei by the water molecules around the ions. The shielding constant is σ(85Rb+) = -2.11 (2) · 10-4 . This yields a general atomic reference scale for the chemical shift of rubidium in the liquid and solid states and the possibility of comparing experimental and theoretical shielding constants.

107Ag and 109Ag Nuclear Magnetic Resonance Studies of Ag+ Ions in Aqueous Solutions

1973 ◽  
Vol 28 (11) ◽  
pp. 1753-1758 ◽  
Author(s):  
C.-W. Burges ◽  
R. Koschmieder ◽  
W. Sahm ◽  
A. Schwenk
Keyword(s):  
Aqueous Solutions ◽  
Infinite Dilution ◽  
Magnetic Moments ◽  
Relaxation Times ◽  
Isotopic Effect ◽  
Water Molecules ◽  
Resonance Frequencies ◽  
Beam Experiment ◽  
The Difference ◽  
Limits Of Error

The NMR lines of 107Ag and 109Ag have been investigated in aqueous solutions of AgF, AgNO3, and AgClO4. The ratio of the Larmor frequencies of 109Ag and 107Ag has been measured in various samples: ν(109Ag)/ν(107Ag) = 1.149 639 7 (8). No primary isotopic effect was to be detected within these limits of error (0.7 ppm). This ratio yields the hyperfine structure anomaly 107⊿109 = − 0.004127 7(7). The concentration dependence of the chemical shift of the 107Ag and 109Ag resonance frequencies was determined. Using this dependence, the ratios of the Larmor frequencies of the 107Ag and 109Ag nuclei for infinite dilution relative to the resonance frequency of 73Ge in GeCl4 are given. The magnetic moments of the 107Ag+ and 109Ag+ ions merely surrounded by water molecules are μ(107Ag+) = − 0.113 045 3(9) μN and μ(109Ag+) = − 0.129 961 5(10) μN without diamagnetic corrections. These values are compared with the result of an atomic beam experiment, the difference of the moments is due to the shielding of the silver nuclei by water molecules around the ions. The shielding constant is σ* (Ag+ in H2O vs. Ag atom) = − 0.000 94(17). Preliminary values of the relaxation times are given.

scholarly journals Multinuclear Magnetic Resonance Study of Sodium Salts in Water Solutions

2019 ◽  
Vol 5 (4) ◽  
pp. 68 ◽  
Author(s):  
Włodzimierz Makulski
Keyword(s):  
Experimental Data ◽  
Magnetic Resonance ◽  
Magnetic Moments ◽  
Resonance Method ◽  
15N Nmr ◽  
Water Solutions ◽  
Nuclear Magnetic Moments ◽  
Shielding Constants ◽  
15N Nmr Spectroscopy ◽  
Nuclear Magnetic

The small amounts of gaseous 3He dissolved in low concentrated water solutions of NaCl, NaNO3 and NaClO4 were prepared and examined by 3He-, 23Na-, 35Cl- and 15N-NMR spectroscopy. This experimental data, along with new theoretical shielding factors, was used to measure the 23Na nuclear magnetic moment against that of helium-3 μ(23Na) = +2.2174997(111) in nuclear magnetons. The standard relationship between NMR frequencies and nuclear magnetic moments of observed nuclei was used. The nuclear magnetic shielding factors of 23Na cation were verified against that of counter ions present in water solutions. Very good agreement between shielding constants σ(3He), σ(23Na+), σ(35Cl‒), σ(35ClO4‒), σ(15NO3‒) in water at infinite dilution and nuclear magnetic moments was observed for all magnetic nuclei. It can be used as a reference nucleus for calculating a few other magnetic moments of different nuclei by the NMR method. An analysis of new and former μ(23Na) experimental data obtained by the atomic beam magnetic resonance method (ABMR) and other NMR measurements shows good replicability of all specified results. The composition of sodium water complexes was discussed in terms of chemical equilibria and NMR shielding scale.

scholarly journals The Radiofrequency NMR Spectra of Lithium Salts in Water; Reevaluation of Nuclear Magnetic Moments for 6Li and 7Li Nuclei

2017 ◽  
Author(s):  
Włodzimierz Makulski
Keyword(s):  
Dipole Moments ◽  
Magnetic Moments ◽  
Resonance Method ◽  
Resonance Spectroscopy ◽  
Water Solutions ◽  
Nuclear Magnetic Moments ◽  
Magnetic Resonance Method ◽  
Concentration Dependences ◽  
Shielding Constants ◽  
Nuclear Magnetic

The LiCl and LiNO3 water solutions in the presence of small amounts of 3-helium have been investigated by means of multinuclear resonance spectroscopy. The resulting concentration dependences of the 3He, 6,7Li+, 14NO3¯ and 35Cl¯ resonance radiofrequencies are reported in the infinite limit. This data along with new theoretical corrections of shielding lithium ions was analyzed by a known NMR relationship method. Consequently, the nuclear magnetic moments of 6Li and 7Li were established against that of the helium-3 dipole moment: μ(6Li)=+0.822046(5)μN and μ(7Li)=+3.256418(20)μN. The new results were shown to be very close to the previously obtained values of the (ABMR) atomic beam magnetic resonance method. This experiment proves that our helium method is well suited for establishing dipole moments from NMR measurements performed in water solutions. This technique is especially valuable when gaseous substances of the needed element are not available. All shielding constants of species present in water solutions are consistent with new nuclear magnetic moments and these taken as a reference. Both techniques – NMR and ABMR – give practically the same results providing that all shielding corrections are properly made.

Corrections to the Baseline Distortions in the OH-Stretch Region of Aqueous Solutions

1994 ◽  
Vol 48 (1) ◽  
pp. 107-112 ◽  
Author(s):  
Wolfgang B. Fischer ◽  
Hans H. Eysel ◽  
Ole F. Nielsen ◽  
John E. Bertie
Keyword(s):  
Raman Scattering ◽  
Aqueous Solutions ◽  
Raman Spectra ◽  
Pure Water ◽  
Water Molecules ◽  
Ir Absorption ◽  
Difference Spectra ◽  
Dilute Aqueous Solutions ◽  
The Difference ◽  
Sulfuric Acid Solutions

The intensity gains or intensity losses of the OH-stretch vibrations and their changes of band shapes as observed in IR or Raman spectra of dilute aqueous solutions of carboxylic acids, amino acids, and amines were able to be simulated. The difference spectra of the type {sample solution} – {standard} x {empirical factor} displayed essentially flat baselines throughout the OH-stretch region of isotropic Raman scattering. Peaks of the solute spectra which had been hidden by the OH-stretch contour emerged from the background. At concentrations below 1 M, pure water was the standard. Distortions of the isotropic Raman spectra at higher solute concentrations (1 M to 4 M) could be mimicked by phosphoric acid or sulfuric acid solutions as standards. The influence of solutes on the reorientational motions of water molecules made baseline corrections of anisotropic Raman scattering and IR absorption of the more concentrated solutions difficult, if not impossible.

Long-Term Correlations In Diffusive Motion Of Water Molecules And Rare Gas Atoms In Helium And Argon Aqueous Solutions

2015 ◽  
Vol 60 (8) ◽  
pp. 757-763 ◽  
Author(s):  
V.P. Voloshin ◽  
◽  
G.G. Malenkov ◽  
Yu.I. Naberukhin ◽  
◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Rare Gas ◽  
Water Molecules ◽  
Diffusive Motion ◽  
Rare Gas Atoms

The metachor as a characteristic of the association of electrolytes in aqueous solutions

1984 ◽  
Vol 49 (5) ◽  
pp. 1061-1078 ◽  
Author(s):  
Jiří Čeleda ◽  
Stanislav Škramovský
Keyword(s):  
Aqueous Solutions ◽  
Apparent Volume ◽  
Solutions Of Electrolytes ◽  
Molal Volumes ◽  
The Difference ◽  
High Concentrations ◽  
Experimental Values ◽  
Suitable Characteristic ◽  
Association Of Ions ◽  
Very High

Based on the earlier paper introducing a concept of the apparent parachor of a solute in the solution, we have eliminated in the present work algebraically the effect which is introduced into this quantity by the additivity of the apparent molal volumes. The difference remaining from the apparent parachor after substracting the contribution corresponding to the apparent volume ( for which the present authors suggest the name metachor) was evaluated from the experimental values of the surface tension of aqueous solutions for a set of 1,1-, 1,2- and 2,1-valent electrolytes. This difference showed to be independent of concentration up to the very high values of the order of units mol dm-3 but it was directly proportional to the number of the free charges (with a proportionality factor 5 ± 1 cm3 mol-1 identical for all studied electrolytes). The metachor can be, for this reason, a suitable characteristic for detection of the association of ions and formation of complexes in the solutions of electrolytes, up to high concentrations where other methods are failing.

Konkurrierende Liganden: Theophyllin als nicht- und stark koordinierender Ligand in Quecksilber(II)-Komplexen / Competing Ligands: Theophylline as Non- and Strongly Coordinating Ligand in Mercury(II) Complexes

2006 ◽  
Vol 61 (6) ◽  
pp. 758-765 ◽  
Author(s):  
Matthias Nolte ◽  
Ingo Pantenburg ◽  
Gerd Meyer
Keyword(s):  
Oxygen Atom ◽  
Water Molecule ◽  
Aqueous Solutions ◽  
Single Crystal ◽  
Coordination Polymers ◽  
Water Molecules ◽  
Slow Evaporation ◽  
Monoclinic Symmetry ◽  
X Ray ◽  
Chloride Ligand

[{Hg(CF3)2}(ThpH)(H2O)](H2O) (1), [{Hg4(Thp)4}(ClO4)4(H2O)8](H2O)4 (2), [{Hg(ThpH)2} (NO3)](NO3) (3) and {Hg(Thp)Cl}(H2O) (4) (ThpH = theophylline, C7H8N4O2) have been synthesized by slow evaporation of aqueous solutions of the mercuric salts Hg(CF3)2, Hg(ClO4)2, Hg(NO3)2, or HgCl2 and theophylline. Their crystal structures were determined on the basis of single crystal X-ray data. The coordination polymers 1 and 2 crystallize with triclinic symmetry, P1̅ (no. 2), with a = 468.8(2), b = 1256.4(5), c = 1445.5(6) pm, α = 67.15(3), β = 89.21(3), γ = 89.40(3)° and a = 833.6(1), b = 1862.7(2), c = 2182.9(2) pm, α = 111.61(1), β = 90.98(1), γ = 95.51(1)°, respectively. 3 and 4 crystallize with monoclinic symmetry, Pc (no. 7), a =1194.1(1), b=1258.8(2), c=735.5(2) pm, β =96.96(2)° and P21/n (no. 14), a=1069.0(2), b =911.6(1), c=1089.9(2) pm and β = 96.87(2)°. In 1 the theophylline molecules are non-coordinating to mercury and leave the Hg(CF3)2 molecule unchanged. Only weak electrostatic attractions to one keto-oxygen atom of theophylline and one water molecule hold this co-crystallisate together. In 2, the theophyllinate anion, Thp−, strongly coordinates with both N(7) and N(9) to HgII forming a large ring with eight Hg atoms that incorporates the water molecules. One sort of nitrate ions in 3 is weakly attached to HgII with the theophylline molecules still bound strongly through N(9). The chloride ligand and the theophyllinate ion seem to have the same strengths as ligands in 4 as they are both attached to HgII with the shortest distances possible

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