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Artículo
Microscopic dynamics of glycerol in its crystalline and glassy states
(American Physical Society, 1996)
The dynamics of crystalline glycerol are studied by means of Raman spectroscopy and lattice dynamics calculations employing a semiflexible model to represent the low-lying molecular vibrations. The latter is validated ...
Artículo
1,1,3,3-tetramethylguanidinium dihydrogenorthophosphate
(International Union of Crystallography, 2000)
In the title compound, C 5 H 14 N 3 + H 2 PO 4 ˇ , the cation has a central guanidinium fragment with a planar geometry, as expected for a central C sp 2 atom with a small ...
Artículo
Structure of l-(p-Ethoxyphenyl)-1,3-dihydro-3-phenyl-2H-benzimidazole-2-thione, C2IHlaN2OS
(International Union of Crystallography, 1984)
Mr=346-4, orthorhombic, P212121, a= 7.600(1), b= 11.132(2), c=20.767 (3)A, v= 1756.9(5)A 3, z=4, Dx=1.31Mgm -3, 2(CuKct) =.1.5418/k, /~= 1.67mm -1, F(000)=728, T= 300 K. Final R = 0.049 for 1531 observed independent ...
Artículo
Incommensurate instability and lattice dynamics of potassium selenate within a semiempirical rigid-ion model
(American Institute of Physics Publising LLC, 1990)
The lattice dynamics of potassium selenate is analyzed using a rigid-ion model with the selenate groups reduced to rigid bodies. The interatomic forces have been adjusted only using static structural data. The number of ...
Artículo
Lattice Dynamical Calculation of First-Order Thermal Diffuse Scattering in Phenothiazine
(International Union of Crystallography, 1985)
A computer program has been developed to calculate first-order thermal diffuse scattering (TDS) intensity from eigenvectors and eigenvalues of the dynamical matrix obtained within the harmonic approximation with an ...
Artículo
Role of low-frequency vibrations on sound propagation in glasses at intermediate temperature
(American Physical Society, 2000)
We report measurements of the temperature dependence of the sound attenuation and the fractional change in sound velocity for the glass (G) and orientational-glass (OG) phases of polymorphic ethanol. Strikingly similar ...
Artículo
Structure of 1,3-Dihydro-4-[(2R)-2,5-dihydro-2-furyl]-3-phenyl-l-(p-tolyl)-2H-imidazole- 2-thione, C20HlsN2OS
(International Union of Crystallography, 1985)
Mr=334.4, orthorhombic, P212~2 ~, a= 9.366(4), b=20.616(5), c=9.137(4)A, V= 1764 (1) A 3, Z = 4, D x = 1.26 Mg m -3, 2(Mo Ka) = 0.7107 A, g = 0.18 mm -~, F(000) = 704, T= 300 K, final R--0.056 (wR =0.052) for 1979 ...
Artículo
Benzyltrimethylammonium dihydrogen orthophosphate monohydrate
(International Union of Crystallography, 2005)
The title compound, C 10 H 16 N + H 2 PO 4 H 2 O, crystallizes in the centrosymmetric space group P 2 1 / c with two independent molecules in the asymmetric unit. Therefore, nonlinear ...
Artículo
Collective excitations in liquid methanol: A comparison of molecular, lattice-dynamics, and neutron-scattering results
(American Institute of Physics, 1992)
The collective dynamics of liquid methanol‐d4 is studied by means of molecular‐dynamics simulation. The model potential is validated by means of lattice energy calculations and shows a very good agreement with the ...
Artículo
Evidence for a supercooled plastic-crystal phase in solid ethanol
(American Physical Society, 1996)
The existence of an orientationally disordered cubic phase of solid ethanol is revealed by x-ray diffraction and Raman spectroscopic measurements. Such a phase, whose existence was postulated some time ago on the basis of ...