INVESTIGADORES
BONETTO fernando Jose
artículos
Título:
Time scale of short range order fluctuation in the isotropic phase of butylcyano-phenylcyclohexane liquid crystal
Autor/es:
F. VACA CHAVEZ; F. BONETTO; D. J. PUSIOL
Revista:
CHEMICAL PHYSICS LETTERS
Editorial:
Elsevier
Referencias:
Lugar: Amsterdam, The Netherlands; Año: 2000 vol. 330 p. 368 - 372
ISSN:
0009-2614
Resumen:
The NMR spin-lattice relaxation time at three Larmor frequencies ( 28 MHz, 1.235 MHz and 48 kHz) in the isotropic phase of butylcyano-phenylcyclohexane has been measured in the temperature range close to the isotropic-nematic phase transition. Spin-lattice relaxation mechanisms provided by both individual reorientational fluctuations and fluctuations of the local director can be distinguished at the different Larmor frequency scales. We conclude that the Landau-De Gennes theory for the weak first order nematic-isotropic phase transition, together the low frequency approximation can be applied if the experiment is carried out at Larmor frequencies in the kHz range.
