Self-diffusion coefficients of TBBA : comparison between neutron and NMR results
نویسندگان
چکیده
2014 The average self-diffusion coefficients have been measured by neutron quasi-elastic scattering using the back-scattering technique, in the smectic A, nematic and isotropic phases of TBBA. The results are compared with previous neutron and NMR results. We find that the agreement is good for the smectic A and isotropic phases only. We deduce that the NMR results are probably incorrect for the nematic phase. A simple model for selfdiffusion in the smectic A and nematic phases which satisfactorily fits our results is also presented. LE JOURNAL DE PHYSIQUE LETTRES TOME 40, 15 NOVEMBRE 1979, Classification Physics Abstracts 61.30 61.12 76.60
منابع مشابه
Self diffusion coefficients of TBBA
2014 The diffusion coefficients D~ and D~ have been measured by a two pulse NMR spin echo with rotatable pulsed field gradient in the nematic regime of TBBA. In this range we find D~ /D~ ~ 3. The diffusion process in both the nematic and the smectic A phases is discussed briefly. LE JOURNAL DE PHYSIQUE TOME 38, MARS 1977,
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