Theory of Solid Hydrogen Mixture. I. Distribution of Local Order Parameters, NMR Line Shapes and Relaxation Times

A cw high-power ENDOR spectrometer is described. Freed's theory of coherence effects on ENDOR line shapes of free radicals in solution was tested with cw NMR fields up to 30 Gauss. The neutral radical Perinaphthenyl (PNT) with groups of three and six equivalent protons served as example. A satisfactory agreement with the theory was found, even in quantitative terms. Very reasonable values for relaxation times T1e , T2e and T1n of the PNT could be determined by fitting Te-1/We, Wn/We and using measured values for BMW, BNMR and the EPR line width.

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Simulated NMR Line Shapes for Random Ordering in Solid Hydrogen Films

10.1063/1.2354738 ◽

2006 ◽

Author(s):

Kiho Kim ◽

J. R. Bodart ◽

N. S. Sullivan

Keyword(s):

Solid Hydrogen ◽

Line Shapes

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Local order parameters for symmetry fractionalization

New Journal of Physics ◽

10.1088/1367-2630/ab4fff ◽

2019 ◽

Vol 21 (11) ◽

pp. 113016 ◽

Cited By ~ 2

Author(s):

José Garre-Rubio ◽

Sofyan Iblisdir

Keyword(s):

Order Parameters ◽

Local Order

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Local bond order parameters for accurate determination of crystal structures in two and three dimensions

Physical Chemistry Chemical Physics ◽

10.1039/c8cp05248d ◽

2018 ◽

Vol 20 (42) ◽

pp. 27059-27068 ◽

Cited By ~ 8

Author(s):

Hossein Eslami ◽

Parvin Sedaghat ◽

Florian Müller-Plathe

Keyword(s):

Crystal Structures ◽

Bond Order ◽

Accurate Determination ◽

Three Dimensional ◽

Order Parameters ◽

Three Dimensions ◽

Local Order ◽

Crystalline Structures

Local order parameters for the characterization of liquid and different two- and three-dimensional crystalline structures are presented.

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Comment on ‘‘Quadrupolar glass freezing in solid hydrogen: Distribution functions for the orientational order parameters’’

Physical Review B ◽

10.1103/physrevb.51.3965 ◽

1995 ◽

Vol 51 (6) ◽

pp. 3965-3965

Author(s):

K. Walasek

Keyword(s):

Orientational Order ◽

Solid Hydrogen ◽

Order Parameters ◽

Distribution Functions ◽

Hydrogen Distribution ◽

Quadrupolar Glass

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Analysis of diffuse scattering from the mineral mullite

Journal of Applied Crystallography ◽

10.1107/s0021889894002220 ◽

1994 ◽

Vol 27 (5) ◽

pp. 742-754 ◽

Cited By ~ 16

Author(s):

B. D. Butler ◽

T. R. Welberry

Keyword(s):

Diffuse Scattering ◽

Real Space ◽

Order Parameters ◽

Scattering Data ◽

Local Order ◽

Near Neighbour ◽

Diffuse Intensity ◽

Space Model ◽

Least Squares Techniques ◽

Space Volume

A full reciprocal-space volume of diffuse scattering data from a single-crystal of the mineral mullite, Al2(Al2 + 2x Si2 − 2x )O10 − x , x = 0.4, was collected. These data were analysed using least-squares techniques by writing an equation for the diffuse scattering that involves only the local order between vacancies on specific oxygen sites in the material. The effect of the large, but predictable, cation shifts on the diffuse intensity is taken account of in the coefficients of the oxygen-vacancy short-range-order intensities. This analysis shows that the vacancies are negatively correlated at the near-neighbour ½ 〈110〉, [110], 〈001〉 and 〈011〉 interatomic vectors and positively correlated along the 〈010〉, 〈101〉, ½ 〈112〉 and ½ 〈310〉 vectors. Subsequent Monte Carlo modelling of the structure based on these local-order parameters demonstrates that the structure of mullite is dominated by effective near-neighbour vacancy–vacancy repulsive interactions. A real-space model of mullite is presented that is approximately consistent with the measured local-order parameters.

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