## 抄録

Fluctuations of lamellar structure prior to a [Formula Presented] transition in a nonionic surfactant–water system has been investigated by means of small-angle x-ray scattering (SAXS) and differential scanning calorimeter measurements. For large [Formula Presented] [Formula Presented] where T is the temperature and [Formula Presented] the [Formula Presented] transition temperature) in the lamellar phase, the SAXS profiles can be described by a Caillé correlation function for undulating lamellar structure. Approaching the temperature to the [Formula Presented] an excess diffuse scattering grows at the lower Q (Q is the magnitude of scattering vector) side of the first lamellar peak. Highly oriented lamellar samples revealed that the excess diffuse scattering arises from in-plane density fluctuations. We attribute this diffuse scattering to the perforation fluctuation layer (PFL) structure and we show that the PFL is an equilibrium structure. At [Formula Presented] the PFL transformed to the gyroid phase through a transient ordered structure having a rhombohedral symmetry.

本文言語 | English |
---|---|

ページ（範囲） | 6865-6874 |

ページ数 | 10 |

ジャーナル | Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics |

巻 | 62 |

号 | 5 |

DOI | |

出版ステータス | Published - 2000 1 1 |

外部発表 | はい |

## ASJC Scopus subject areas

- 統計物理学および非線形物理学
- 数理物理学
- 凝縮系物理学
- 物理学および天文学（全般）