Coherent Soft-X-Ray Dynamic Light Scattering from Smectic-A Films
نویسندگان
چکیده
We have used coherent soft-x-ray dynamic light scattering at the Bragg peak to measure the thermally driven layer fluctuations in freely suspended films of five different smectic-A liquid crystals: 4O.8, 7O.7, 8CB, 8OCB, and 10OCB. The measured relaxation times at a scattering wave vector corresponding to the interlayer spacing (2pq21 ø 30 Å) ranged from 2 to 60 ms for films from 4 to 50 mm thick. Thus, we have achieved the same time resolution as conventional laser dynamic light scattering, but with 100 times higher spatial resolution. [S0031-9007(98)08149-6]
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