X-RAY-SCATTERING STUDY OF SMECTIC ORDERING IN A SILICA AEROGEL

被引：108

作者：

CLARK, NA

BELLINI, T

MALZBENDER, RM

THOMAS, BN

RAPPAPORT, AG

MUZNY, CD

SCHAEFER, DW

HRUBESH, L

机构：

[1] UNIV PAVIA,DIPARTIMENTO ELETTR,I-27100 PAVIA,ITALY

[2] EXXON RES & ENGN CO,ANNANDALE,NJ 08801

[3] SANDIA NATL LABS,ALBUQUERQUE,NM 87185

[4] LAWRENCE LIVERMORE NATL LAB,LAWRENCE LIVERMORE LAB,LIVERMORE,CA 94551

来源：

PHYSICAL REVIEW LETTERS | 1993年 / 71卷 / 21期

关键词：

D O I：

10.1103/PhysRevLett.71.3505

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We have studied, via x-ray scattering, the nematic to smectic-A (NA) translational ordering of the liquid-crystal-forming compound octylcyanobiphenyl (8CB) incorporated into the pores of a silica aerogel. We find that the aerogel dramatically alters 8CB phase behavior, eliminating the NA transition found at T=T(NA)=33.7-degrees-C in bulk samples and replacing it by a short range smectic ordering having a correlation length which at T(NA) is xi is similar to 40 angstrom, much smaller than the aerogel pore and nematic domain size xi(p) is similar to 200 angstrom. As T is lowered this smectic disorder is eliminated from the pores, xi increasing continuously over a 20-degrees-C range to saturate at xi(p) for T < T(NA) -20-degrees-C.

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页码：3505 / 3508

页数：4

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