scholarly journals Ultrafast Laplace NMR to study metal-ligand interactions in reversible polarisation transfer from parahydrogen

2021 ◽  
Author(s):  
Ben. J. Tickner ◽  
Vladimir V. Zhivonitko ◽  
Ville-Veikko Telkki
Keyword(s):  
Molecular Structure ◽  
Relaxation Times ◽  
The Self ◽  
Self Diffusion ◽  
Structure And Dynamics ◽  
Relaxation Parameters ◽  
Diffusion Constants ◽  
Ligand Interactions ◽  
And Diffusion ◽  
Metal Ligand

Laplace Nuclear Magnetic Resonance (NMR) can determine relaxation parameters and diffusion constants, giving valuable information about molecular structure and dynamics. Information about relaxation times (T1 and T2) and the self-diffusion...

scholarly journals Elucidation of Structure and Dynamics in Biopolymer Solutions Through Measurements of Relaxation Times and Diffusion Coefficients by NMR

2003 ◽  
Vol 60 (6) ◽  
pp. 269-279 ◽  
Author(s):  
Shingo MATSUKAWA ◽  
Qiujn ZHANG ◽  
Kinuko ABE ◽  
Yuri WATANABE ◽  
Tokuko WATANABE
Keyword(s):  
Diffusion Coefficients ◽  
Relaxation Times ◽  
Structure And Dynamics ◽  
Biopolymer Solutions ◽  
And Diffusion

Ionic Dynamics in LiNO2 Studied by 7Li and 15N Solid NMR

1999 ◽  
Vol 54 (8-9) ◽  
pp. 519-523 ◽  
Author(s):  
Hisashi Honda ◽  
Shin'ich Ishimaru ◽  
Ryuichi Ikeda
Keyword(s):  
Relaxation Times ◽  
Activation Parameters ◽  
Lattice Relaxation ◽  
The Self ◽  
Spin Lattice Relaxation ◽  
Plastic Crystal ◽  
Self Diffusion ◽  
Spin Lattice ◽  
Solid Nmr ◽  
Temperature Dependences

The temperature dependences of 7Li and 15N NMR spin-lattice relaxation times and spectra in LiNO2 were measured in the range 120 K -473 K (m.p.). The 180°-flip motion of NO2-- ions along or perpendicular to the molecular C2 -axis and the self-diffusion of Li+ ions (activation energies of 42 -44 and 100 kJ mol-1 , respectively) were observed in this range. From the comparison of the observed activation parameters with those reported for plastic phases of alkali metal nitrites, a new characteristic of the plastic crystal was obtained.

scholarly journals Molecular Structure and Dynamics of Water on Pristine and Strained Phosphorene: Wetting and Diffusion at Nanoscale

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Wei Zhang ◽  
Chao Ye ◽  
Linbi Hong ◽  
Zaixing Yang ◽  
Ruhong Zhou
Keyword(s):  
Molecular Structure ◽  
Structure And Dynamics ◽  
And Diffusion

Point Defects and Diffusion in Ni3Ga

1998 ◽  
Vol 527 ◽  
Author(s):  
T. IKEDA ◽  
A. Almazouzi ◽  
A. Funao ◽  
H. Numakura ◽  
M. Koiwa ◽  
...  
Keyword(s):  
Point Defects ◽  
Positron Lifetime ◽  
Major Element ◽  
Tracer Diffusion ◽  
The Self ◽  
Self Diffusion ◽  
Order Of Magnitude ◽  
Constituent Elements ◽  
Tracer Diffusion Coefficients ◽  
And Diffusion

ABSTRACTThe properties of intrinsic point defects and the self-diffusion behaviour of the constituent elements in Ni3Ga have been studied by positron annihilation, tracer diffusion and interdiffusion experiments. Thermal vacancies have been detected by positron lifetime measurements for specimens quenched from high temperatures. The vacancy formation energy is in the range between 1.7 and 1.8 eV, and is not dependent strongly on the composition. The tracer diffusion coefficients of Ni and Ga are of the same order of magnitude, and the interdiffusion coefficient is about 10 times larger than the diffusion coefficient of Ni. The diffusion in Ni3Ga has been found to satisfy the Darken-Manning equation, as expected from the model of the self-diffusion in this type of materials, where both the species of atoms are assumed to migrate primarily in the sub-lattice of the major element via the ordinary vacancy mechanism.

Atomistic Simulation of the Self-Diffusion in Very Thin Cu (001) Film by Using MAEAM

2014 ◽  
Vol 1015 ◽  
pp. 37-41
Author(s):  
Yan Ni Wen ◽  
Xiao Bin Fang ◽  
Xiao Fei Jia
Keyword(s):  
Thin Film ◽  
Atomistic Simulation ◽  
Md Simulation ◽  
Atomic Layer ◽  
The Self ◽  
Vacancy Formation ◽  
Embedded Atom Method ◽  
Self Diffusion ◽  
Embedded Atom ◽  
And Diffusion

The self-diffusion in very thin Cu (001) film that formed by 2~11 atomic layers have been studied by using modified analytic embedded atom method (MAEAM) and a molecular dynamic (MD) simulation. The vacancy formation is the most easily in of Cu (001) thin film formed by any layers. The vacancy formation energy 0.5054eV in of the Cu (001) thin film formed by layers is the highest in all the values in the ones that formed by layers. The vacancy in and 3 is easily migrated to layer, and the vacancy in is easily migrated in intra-layer, and the vacancy in is easily migrated to when the corresponding atomic layer is existed. The vacancy formation and diffusion will not be affected by the atomic layer when the Cu (001) thin film is formed by more than ten layers ().

Permeability in Relation to Viscosity and Structure of Rubber

1942 ◽  
Vol 15 (3) ◽  
pp. 537-544 ◽  
Author(s):  
Richard M. Barrer
Keyword(s):  
Viscous Flow ◽  
Thermal Energy ◽  
Diffusion Constant ◽  
The Self ◽  
Self Diffusion ◽  
Functional Relations ◽  
Diffusion Media ◽  
Entropy Of Activation ◽  
Arrhenius Energy ◽  
And Diffusion

Abstract Some properties of flow of solutes in and through rubbers are outlined. These properties indicate that, due to fluctuations of thermal energy, activated zones exist in certain polymers, of which viscous flow and diffusion are a consequence. A simple statistics of activated zones has been given, and from it equations are obtained for ΣN, D, Ds, and η, denoting respectively the total number of activated zones in rubber, the diffusion constant of simple solutes in the polymer, the self-diffusion constant of rubber, and its viscosity. Functional relations are predicted between log Do, log ηo, or ΔS* (the entropy of activation) and the Arrhenius energy of activation for diffusion or viscous flow. The available data clearly demonstrate this relationship. They also indicate no discontinuity between rubbers and liquids as diffusion media.

scholarly journals Aggregation Behavior of 6-Isocassine and N-Methyl-6-Isocassine: Insights into the Biological Mode of Action of Lipid Alkaloids

2016 ◽  
Vol 11 (11) ◽  
pp. 1934578X1601101
Author(s):  
Luis Reina ◽  
Gualberto Bottini ◽  
Zohra Bennadji ◽  
Vittorio Vinciguerra ◽  
Fernando Ferreira ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Diffusion Coefficients ◽  
Mode Of Action ◽  
Aggregation Behavior ◽  
The Self ◽  
Self Diffusion ◽  
And Diffusion

The aggregation behavior of 6-isocassine and N-methyl-6-isocassine, two piperidin-3-ol alkaloids isolated respectively from the barks of Prosopis nigra and P. affinis, was investigated using a combination of NOE experiments and diffusion measurements in solvents of varying polarity and hydrogen bonding capacity. While the NOE enhancements for N-methyl-6-isocassine are positive, regardless of the solvent, those for 6-isocassine shift from negative to positive when going from chloroform- d to methanol- d 4 solution. In addition, despite the self-diffusion coefficients of both compounds being virtually identical in methanol- d 4, N-methyl-6-isocassine diffuses nearly twice as fast as the non-methylated alkaloid in chloroform- d. The changes in rotational and translational dynamics observed between solvents for 6-isocassine suggest that the molecule forms dimeric head-to-head aggregates in non-polar aprotic environments, a behavior that could help explain the biological mode of action that has been proposed for this type of alkaloids.

Spin–lattice relaxation in MBBA and MBBA – carbon tetrachloride mixtures

1980 ◽  
Vol 58 (21) ◽  
pp. 2246-2249 ◽  
Author(s):  
Margaret A. Heldman ◽  
D. F. R. Gilson
Keyword(s):  
Relaxation Time ◽  
Carbon Tetrachloride ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
The Self ◽  
Spin Lattice Relaxation ◽  
Correct Order ◽  
Self Diffusion ◽  
Spin Lattice ◽  
Diffusion Constants

The spin–lattice relaxation time has been measured at 33 MHz as a function of temperature for the liquid crystal MBBA and mixtures with carbon tetrachloride. The behaviour of T1, close to the nematic–isotropic transition can be explained if the correct order fluctuation dependence is included. Diffusion constants calculated from fits to the self-diffusion contribution to relaxation are in agreement with existing results.

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