A series of new chiral compounds with a 6-valerolactone ring were synthesized and the physical properties of these compounds as well as the electrical properties of their ferroelectric liquid crystal (FLC) mixtures were investigated. The magnitude of spontaneous polarization ( P I ) in the chiral srnectic C phase (SmC*) was found to be as high as 384 nC/cm' for (2R, 5R)-2-(4'-octyloxybiphenyl-4-carboxy)-5-butyl-6-valerolactone at AT = Tc -T = 5"C, where Tc is the temperature of transition from the isotropic phase to the SmC* phase and T is the temperature at which the experiments were carried out. An FLC mixture containing 2% by weight of the optical isomer, (2S, 5R)-2-(4'-octyloxy-biphenyl-4-carboxy)-5-hexyl-6-valerolactone exhibited a response time as fast as 96 p seconds at 25°C. for an applied square-wave voltage of ? 10 volts. The relationship between the structural properties and the thermal properties, magnitude and polarity of Ps as well as the response times for their FLC mixtures are discussed.

A 6-dimensional grand unified theory with the compact space having the topology of a real projective plane, i.e., a 2-sphere with opposite points identified, is considered. The space is locally flat except for two conical singularities where the curvature is concentrated. One supersymmetry is preserved in the effective 4d theory. The unified gauge symmetry, for example SU(5) , is broken only by the non-trivial global topology. In contrast to the Hosotani mechanism, no adjoint Wilson-line modulus associated with this breaking appears. Since, locally, SU(5) remains a good symmetry everywhere, no UV-sensitive threshold corrections arise and SU(5)-violating local operators are forbidden. Doublettriplet splitting can be addressed in the context of a 6d N = 2 super Yang-Mills theory with gauge group SU(6). If this symmetry is first broken to SU(5) at a fixed point and then further reduced to the standard model group in the above non-local way, the two light Higgs doublets of the MSSM are predicted by the group-theoretical and geometrical structure of the model.

Novel optically active compounds derived from (R)-3-hydroxynonanoic acid as shown in a general formula (I) B 0'' ' 0 211 + I CrlH2n+l (n: 8, 10, or 12; X: -0-, -0CO-, or -COO-; Y: -0CO-, -COO-, -CH,O-, or -OCH,-; AI , A t , B, , or B2: -H or -Cl)have been synthesized and their mesomorphic and ferroelectric properties have been investigated. The kind of mesophases and the transition temperatures depend strongly on the linkage groups and the substituents in the core. The compounds with an unsubstituted core show non-titled smectic mesophases (smectic A or B). The chiral smectic C phase appears in the compounds having a central ester linkage and a chloro-substituent as the A , or B1 position and in the compound having a central -OCH2-linkage and a chloro-substituent at the A , position. The maximum spontaneous polarization (500 pC/m2) was observed in 4-dodecyloxy-3-chlorobenzoyloxyphenyl (R)-3-hydroxynonanoate. The thermal stability of each mesophase and the ferroelectric properties have been discussed from the structural point of view.