Novel Liquid Crystalline Structure in Langmuir Monolayers of Amphiphilic Azobenzene Derivative

Orientational Fluctuations in a Two-Dimensional Smectic-CLiquid Crystal with Variable Density

“…For 0.2 # K B ͞K S # 5, the fit yields values for n and K p K B K S within 10% of the values of n, K S , and K B put into Eq. (8). Therefore, the values of K presented in this Letter represent the geometric mean of the bend and splay elasticities.…”

“…Langmuir monolayers, i.e., monolayers of amphiphilic molecules at an air-water interface, have long been studied as model two-dimensional systems [1]. As a function of temperature and surface pressure, Langmuir monolayers display a variety of phases; x-ray scattering [2][3][4] and microscopy [5][6][7][8] experiments have revealed the microscopic structure of many of these phases. Recently an amphiphilic substance was identified that exhibits a 2D smectic-C phase [8] characterized by quasilong-range orientational order and short-range positional order.…”

“…As a function of temperature and surface pressure, Langmuir monolayers display a variety of phases; x-ray scattering [2][3][4] and microscopy [5][6][7][8] experiments have revealed the microscopic structure of many of these phases. Recently an amphiphilic substance was identified that exhibits a 2D smectic-C phase [8] characterized by quasilong-range orientational order and short-range positional order. The molecules in this phase are tilted from the surface normal; their projection onto the interface defines a 2D director fieldn͑r͒ ͓sin w͑r͒, cos w͑r͔͒, where w is the angle that the projection makes with an arbitrarily defined x axis.…”

Photoisomerization-Induced Orientational Wave Generation in Two-Dimensional Liquid Crystals at the Air-Water Interface

“…We used 4-octyl-4'-(3-carboxytrimethylenoxy) azobenzene (8AZ3), which forms a two-dimensional (2D) SmC liquid crystalline monolayer at the air-water interface [20]. A chloroform solution of 8AZ3 is spread on a carefblly cleaned water surface in a homemade trough with double movable barriers.…”

“…At low surface-pressure region of 0 -11 mN/m, the monolayer forms the SmC phase with strong optical anisotropy and high fluidity [20]. When the film is compressed over the kink at 12mN/m, the SmC structue is replaced by the solid-like texture showing sharp domain boundaries without orientational flicker [20].…”