Chiral liquid crystalline (LC) monomer showing Sc^*, S_A and cholesteric phases was synthesized. Polymer networks having helical structure was obtained by polymerization of the mixtures of the chiral acrylate and LC diacrylate at the cholesteric phase. The helical pitch of the helical networks was found to depend on the polymerization temperature as well as the mixture composition.

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Liquid crystalline mono- and diacrylate monomers which showed a nematic phase were synthesized. By doping small amounts of a chiral dopant in acrylate mixtures, a cholesteric phase was induced. The helical structure in the induced cholesteric phase was frozen in the polymeric films by photopolymerization. The helical polymer networks with an ionic species could be prepared by alkaline hydrolysis of the polymer films.

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We synthesized liquid crystalline (LC) azobenzene compound having an acrylate group. The LC acrylate was dispersed in poly(methyl methacrylate) (PMMA). The morphology of the LC acrylate/PMMA composite films was investigated by differential scanning calorimetry and polarized microscopic observation. The polymerization of the LC acrylate in the composite films was found to depend on the concentration of the LC acrylate in the films.

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Side chain type polyethers containing p-alkoxyphenyl with various alkyl chain length were prepared by the ring opening polymerization of epoxy monomers. The thermal properties of the polyethers containing p-alkoxyphenyl were investigated by optical microscopy measurements, differential scanning calorimetry and X-ray diffractometry. The polyethers containing p-alkoxyphenyl with 3〜12 methylene chain exhibited a bilayer smectic phase. The polyethers consisted of hydrophilic polymer backbone and hydrophobic side chains. Thus collapse pressure and limiting molecular area of the polyethers were examined. The collapse pressure and limiting molecular area of the polyethers depended on the alkoxy chain length in the side chain.

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Side chain type liquid crystalline copolyesters containing alternative electron donar and electron acceptor mesogenic end groups were synthesized. Furthermore, side chain type liquid crystalline copolyesters with a random sequence of the electron donar and electron accepter mesogenic end groups were also prepared. The induced smectic phase was exhibited for the copolyester containing alternate electron donar and electron accepter mesogenic end group in the side chain. The mesomorphic temperature range was influenced by the sequence of the mesogen with the electron donar and electron accepter group. Further, the thermal properties of the mixture of copolyesters with electron donar and electron accepter end groups were investigated. A mixture of 10〜50mol% of copolyesters with polar end groups exhibited an induced smectic phase.

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In this work, we synthesized thiophene monomers containing a mesogenic group at 3-position of the thiophenering in order to incrcease the solubility and the fusibility. Polymers were obtained by the polycondensation reaction with zero valence nickel, zero valence paradium, or zinc, as a catalyst, and examined their phase transition behaviors and electrochemical properties. The polymers were soluble in organic such as chloroform, THF, toluene, DMF. The mesomorphic properties of the polymers were investigated by differential scanning calorimetry and polarized optical microscopy. The polymers containing cyanobiphenyl or cyanophenyl benzoate exhibited nematic phase, while smectic phase showed for the ester bond type polythiophene. The electrochemical properties of the polymers were examined by cyclic voltammogram measurement. The polymers were identified that they were electrochemically active.

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In order to obtain the uniaxially oriented crosslinked polymers with polarized UV irradiation, we synthesized liquid crystalline acrylate monomers and liquid crystalline polymers containing a mesogenic unit and a photo-crosslinkable unit in the same side chain. Mixtures of acrylate monomers with nematic or cholesteric phases, or LC polymers with a nematic phase were photopolymerized at their liquid crystalline phases in the glass cell provided with uniaxially rubbed polyimide layers. After photopolymerization these mesophases were stabilized, and liquid crystalline molecule (5CB)was oriented by the nematic or the cholesteric film.

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The second harmonic genarations of the liquid crystalline main-chain type copolymers of 2-hydroxy-6-naphthoic acid (HNA) with 4-hydroxy-benzoic acid (PHB), with various composition ratios were investigated. SHG of the films was greatly affected not only by polymerization conditions but also by the processing conditions of the films. NLO coefficient d_<exp> of electrically oniented sample is 3-5 times larger than that of mechanically oriented sample (5pm/V). The investigation on the relation between molecular compositions and the hyperpolarizability ( β ) performed by Molecular Orbital Methods clearly supports the idea that the high SHG of a main-chain polymer is mainly originated the additivity of β value of individual unit due to head to tail connection.

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A homologous series of polymer (TB-n) has been prepared from p-terphenyl-4,4'-dicarboxylicacid and α-ω-alkanediols containing 5 to 20 methylene units which can serve as mesogen and flexible spacer group, respectively. TB-n polymers are formed the two different phases depending on the number of intervening methylene units, n. From TB-n with even n, a smectic A phase is formed in which the axis of both the polymer chain and the mesogenic group lie perpendicular to the layers. In contrast, TB-n with odd n formed a smectic C_A where the polymer chains lie perpendicular to the layer but the mesogenic groups are tilted to the layer normal.

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In the preceding paper, we reported new type, of liquid crystalline (LC) epoxy resins cured by mesogenic hardening compounds. In this paper we report that new and novel LC epoxy resins were obtained by reacting LC diepoxide, 4,4'-diglycidylazoxybenzene, with LC hardener, 4,4'-bis( ω -carboxydecanoxy)azoxybenzene, at 140℃ for 5 min, using tri-n-butylamine as a catalyst. From DSC and IR spectral studies, its gelling time was estimated to be about 10 min at 140℃. It is found that this fully cured epoxy resin is a highly ordered crystalline polymer and has a low thermal expansion coefficient.

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It is well known that ether-type dimeric compounds also exhibit pronounced odd-even effects as observed in ester-type ones. So we prepared the ether-type series, di-mPBn, and investigated the mesophase properties. As a result, odd-even behaviours of ether-type dimers appear to be quite unique compared with ester-linkaged materials. The most notable result is that the odd-membered dimers not only show the ftemperature dependence of tilt angle in the region of smectc C_A phase but also form smectic A and nematic phases at higher temperature region. This, observation is unusual in dimeric system, however is normal in monomeric series, and can be explained that bent-molecules contributed to alternate tilt of mesogen do vary their conformatmon with increase the temperature and at last molecular shape becomes almost linear.

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Mesomorphic phase transition and moleculur motion were investigated for the following polyesters; three polyesters of 1,2-bis(ortho-subsituted phenoxy) ethane-4,4'-dicarboxylic acid (PEC) with hydroquinone derivatives, 4-(2-hydroxyethyl) phenol and 4,4'-(hydroxy) diphenyl ether (HPE) and these of 1,4-bis(phenyl) benzene-4,4'-dicarboxylic acid with HPE, and poly(3-phenyl-4-hydroxy benzoic acid) (PHB) and copolyesters of PHB with 4-hydoroxy or 3-chloro-4-hydroxy benzoic acids. Most of these polyesters have a nematic state whose clearing point was higher than 470K. The thermal stability for nematic phase in these polyesters was well explained by the width and rigidity of main backbone chains.

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Polyamides (P(nAPy)) based on a 2,6-diaminopyridine moiety and low molar mass molecules containing carboxylic acid group formed supramolecular liquid crystalline polymers through the double hydrogen bonds. The polyamides were prepared by polycondensation of 2,6-diaminopyridine and alkylenadicarboxylic acid. These polymeric complexes from the polyamides and azobenzene derivatives (Az(p,q)) showed stable liquid crystalline behavior over wide temperature range, while the polyamide itself is nonmesogenic. Liquid crystallinities were also induced by the formation of the hydrogen bonds between polyamides and benzoic acid derivatives (mClOBA). The polymeric complexes exhibited enantiotropic mesophases.

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4'-cyanobiphenyl-4-(2-propenyloxy) cinnamate(CPC) was synthesized as a side chain mesogenic unit containing a cinnamoyl group, and poly[4-(4'-cyanobiphenoxycarbonyl-vinylene)phenyloxypropyl methyl siloxane (PCMS) was prepared by hydrosilylation reaction between CPC and poly(methylsiloxane). The liquid crystalline behaviors of PCMS were investigated by thermal analysis, optical microscopy and X-ray diffraction methods. PCMS exhibited the following phase transition: G 28℃ SB 60℃ SA 140℃ N 189℃ I. When PCMS was liquid-crystallized from the isotropic melt in the electric field of alternating current, the mesogenic side chains were aligned along the electric fields.

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A new type light scattering liquid crystal (LC) texture and its electrooptical characteristics are reported. 180° twisted LC cells filled with long pitch cholesterics (N^*) of d/P₀ (cell thickness/chiral pitch) were prepared by rubbing poly vinyl alcohol layers. By applying a temporal set of voltage of 50v and 0v, the light scattering texture is caused in the cell, and is held long time. It was presumed that this texture was composed of three planar textures with different twist angles of 0° ,180° and 360°. Levels of light scattering change with d/P₀ and d. Transmittance of the cell can be controlled by applying fairly low voltages of 4v to 10v.

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Effects of the chemical structure of a side chain type liquid crystalline oligomer (LCO) on the steepness of an orientational chanse of the nematic director under the application of an electric field curve have been investigated for the (LCO low molecular weight liquid crystal(LC)) composite systems in a nematic state. The (LCO LC) composite using LCO with longer spacer showed the steeper electric response than the composite using LCO with shorter spacer. This indicates that the side chain type LCO with longer alkylspacer can easily form the mechanically stable smectic-type layer. Also, the (LCO LC) composite using LCO with higher degree of polymerization showed the steeper electric response than the composite using LCO with lower degree of polymerization. This indicates that the LCO with higher degree of polymerization can form higher smectic-type continuity along the polymeric main chain.

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When liquid crystal(LC) molecules contact with a polymer surface, the order parameter of LC molecular alilgnment at the (polymer/LC) interface is not always same as that in the bulk region but is dependent on the magnitude of intermolecular interaction with the polymer surface. The degree of LC molecular order at the interface corresponds to + or - shift of the nematic-isotropic phase trasition temperature(TNT) in comparison with the bulk TNT on the basis of Landau-de Gennes theory. In this study, it was confirmed from the phase transition behavior at the (polymer/LC) interface that the interfacial order of LC molecular alignment is strongly dependent on the magnitude of surface frees energy and the aggregation structure of polymers.

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An electric field hysteresis of the light transmittance of the (polymer / liquid crystal) composite should be strongly related to the electric field hysteresis of the polar anchoring strength for orientation of nematic liquid crystalline molecules at the (polymer / liquid crystal)interface. When the nematic liquid crystal in a homeotropic alignment was sandwiched between physically isotropic polymer layer and substrate, the Schlieren texture and the singular surface disclination (Bloch wall) were observed under polarizing optical microscope. The magnitude of the polar anchoring strength, A_polar was evaluated by measuring the width of the Bloch wall, e. The magnitudes of A_polar were evaluated for three types of the (poly(alkylisopropyl fumarate)s / liquid crystal) cells. It was clarified from the time dependence of e after the application of an electric field that the othe two poly(n-alkylisopropyl fumarate)s have smaller A_polar and longer relaxation time of A_polar than poly(diisopropyl fumarate). It was concluded that the magnitude of A_polar and the relaxation time of A_<polar> were decreased with an increase of the thermal mobility of polymer side chain.

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A novel method to evaluated a dynamic anchoring effect of LC at the (polymer/liquid crystal:LC) interface based on nonlinear dielectric analysis has been proposed. This method is appliable to an opaque material because of the only application of an electric field as a probe. A polymer/LC/polymer parallel layer cell was composed of polyimide and 4-cyano-4'-pentylbiphenyl. The nonlinearity of the responding wave of electric charge was measured when an amplitude modulated electric field was applied to the cell. The magnitude of the nonlinearity corresponds to the degree of realignment of LC directors. The realignment behavior of LC directors anchored to the palymer surface could be selectively evaluated by using an amplitude modulated electric field. The magnitude of the nonlinearity was low in a high frequency region of the modulated wave. This indicates that the realignment of LC directors can not follow the amplitude modulation of an electric field with high frequency. It was confirmed from the frequency dependance of the nonlinearity that the LC at the (polymer/LC) interface could follow an electric field stimulation with higher frequency than the bulk LC.

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The high-electric-field technique is a highly reliable method for meauring the out-of-plane anchoring strength at the solid substrate-nematic interface. This paper describes a simplification of this technique which elliminates the need for capacitance measurement at high AC voltages. Combined with an optical compensation, the new schemes opens up the possibility of "anchoring microscope."

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A simple and accurate method of measuring the surface torsional anchoring energy of nematic liquid crystals is proposed. This method is based on the simultaneous determination of the actual twist angle and the cell gap of a twist nematic cell in which the easy axis of the upper and lower substrates are at a particular angle. We evaluated the torsional anchoring energy in fluorinated nematic LC on different alignment layer material. It was found that value of anchoring energy was about 10^-4 J/m².

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In this study, we report the numerical simulation and the experimental results on the electroclinic effect(ECE) in the SmA of phase. In this numerical simulation, we have taken polar and non-polar anchoring energy into account. Furthermore, we have fablicated one side rubbing LC cells and evaluated moleculer tilte angle in the SmA phase. From the microphtograph and optical measurment, it is suggested that our orientational model corresponding to the numerical result is in good agreement with our experimental result.

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We evaluted the azimuthal anchoring strength and the retardation of the orientational films (the rubbed PI orientational films and the Langmuir-Blodgett orientational films). The liquid crystal used was 5CB (MERCK). It was found that the order of the azimuthal anchoring strength of the rubbed PI orientational films was 10^<-5>[J/m^2]. When we had used the clearance as the parameter, the anchoring strength increased a few amount at first, and then it decreased with increasing the rubbing strength. True rubbing-induced optical retardation also showed similar tendency. Then it was found that the azimuthal anchoring strength increased with increasing the rubbing-induced optical retardation.

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We have made isotropic droplet in nematic phase by precisely controlling temperature at the clearing point. The droplets attached to a non-rubbing PI-surface. We confirmed that the theory of surface tension was valid, and obtain the polar anchoring strength by measuring the contact angle.

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Nematic liquid crystal materials being practically used are reviewed focussing on our development; nematics with a C-C double bond, tolans, fluorinated nematics and ethers. Moreover, our recent works on nematics with deuteriated cyclohexane rings, polymer dispersed liquid crystals for a light scattering LCD, polymer stabilized liquid crystals and UV curable liquid crystals for a functional film,are presented. The properties of fluorinated nematic tolans newly developed for a light scattering LCD are discussed.

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The effects of surface polymer chain density and polymer chemical structure have been examined by molecular dynamics simulations of three layer systems of liquid crystal/polymer(oligomer)/graphite. The excluded volume effect with the polyimide domain edges contributed to alignment of the liquid crystal molecules on the sparse polyimide surface. Differences between packed polyamide surface and the corresponding polyimide case were found mainly in the energetics, and the alignment structures were not so different.

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Characteristic parameters are introduced to express a surface energy between liquid crystal and solid surface. Tensor order parameter is applied to the surface by replacing the scaler order parameter to the scaler order at the surface. Easy axis and surface normal unit vector are also used as the characteristic parameter. Using these parameters, the surface energy is expanded in powers. Three individual energy are obtained: polar anchoring energy, modified azimuthal anchoring energy, and these cross term.

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Diffusion process and cis-trans back isomerzation process of a liquid crystal molecule at solid-liquid interface is detected after photoexcitation by the transient grating method with total reflection for the probe light. By comparing these dynamics with those in the bulk phase,it is found that the diffusion rate at the interface is very simmilar to that in the bulk phase but the back isomerization is enhanced at the interface.

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Pretilt angles of fluorinated liquid crystals with deuterated cyclohexane rings were measured. The influence of deuterium atom, alkyl group, alkenyl group and methylene linkage in a liquid crystalline molecular structure on a pretilt angle is discussed.

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A novel method is proposed for mesuring the deviation of director azianuthal angle from the orientation easy axis at the interface between the substrate and an LC layer in a twisted nematic liquid crystal cell. Due to the method the deviation of azimuthal angle is able to measure accurately even in the case when the dispersion of the rotatary power is significant i.e. the retardation Δnd/λ is smaller than the Morguin limit. This method is applied to measure the azimuthal anchoring energy for a nematic liquid crystal algned on the substrate with a pretilt angle higher than 80 degree. As a result an extremely low azimuthal anchoring energy in the order of 10^-9[J/m²] was obtained.

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The alignment mechanism on LC molecules or UV- exposed polymer surface has been studied. We investigate pretilt angle dependence of rubbed alkyl-branched polyimide LC cells on the amount of UV exposure. Upan UV exposure on the LC- cell, the pretilt angle is increased, and the result is considered to be due to the change of the polyimide surface.

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Pretilt angles and their tilt directions in the flow aligned nematic liquid crystal (LC) cells coated with PI alignment lavers are measured bv a crvstal rotation method and magnetic null method. Very low or 0 pretilt angles are observed in the LC cells prepared using lower pretilt PI layers. On the other hand, high pretilt angles more than 10〜20° are obtained in the LC cell prepared using high pretilt PI layers and the molecular orientation becomes a bend structure.

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The pretilt angle and the anchoring strength are one of the most important parameter in LCDs. However, in the case of amorphous and homeotropic alignment LCDs, it is difficult to evaluate these parameter by means of conventional measurement method due to their non-umniformity of the directors under the applied voltages. We reported the relationship between capacitance versus applied voltage (C-V) characteristics and the polar anchoring strength. In this paper, we report the evaluation method of the pretilt angle and the polar anchoring strength of these LCDs simultaneously by fiting the theoretical values to the data obtained by the measurement of C-V characteristics of these LCDs. The theoretical values are calculated by using a computer simulation based on the elastic continuum theory.

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We have investigated and modelized mechanism of photo-induced LC alignment using PI films by measuring IR and UV absorption spectra and observing the LC alignment direction depending on the wavelength of irradiated UV light. We have been engaged in the research on generating high pretilt angles for practical use such as TN-LCD. We found that the high pretilt angle was generated by introducing "bulky repeating units" having long chain alkyl branches and the pretilt angle can be controlled by adjusting the concentration of these units. Two methods were adopted to introduce the "bulky repeating units" into the polyimide structure; one is the chemically copolymerization method and the other is only adding and mixing these units. Almost the same effect for generating the high pretilt angles was obtained for both methods although there is a significant difference in degree of the obtained pretilt angles.

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Influence of polyimide alignment films on accumulated DC charge in LC cell was studied. In this experiments, when the surface polarity of alignment layer increased, the accumulated DC charge in LC cell increased. This results suggested that the accumullted DC charge was influenced by forming electric double layer which depends on polar molecules of poiyimide surface. And the polyimide structures for decreasing accumulated DC charge were also studied.

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The complex dielectric constants of (s)-hexakis(4-(4'-(6-methyl)octyloxy)biphenoxy)cyclotriphosphazene(SMOCP) were measured in the frequency range between5 Hz and 100 kHz. The maximum of dielectricconstants ε" and losses ε" were found around T-T_c = 2.0 K between 5 and 400 Hz, in which T_c is S_C -I phase transition temperature. This result suggests the existence of a new Currie point or some dielectric relaxation.

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Ferroelectric liquid crystals are of considerable theoretical and technological interest. It has so far been recognized that a tilted smectic phase made up of chiral molecules can be ferroelectric. However considering that the most essential thing is to attach the polar symmmetry to systems, we can say that ferroelectric liquid crystal do not necessarily to be chiral. We descrive a distinct ferroelectric smectic liquid crystal which is formed from the aciral molecules with the banana shape. The origin of the ferroelectricity is ascribed to the C₂v polar symmetry which is produced by the efficient packing of the banan shaped molecules into a smectic layer. This is the first obvious example of ferroelectricity in achiral smectic phase which is ascribed to the C₂v symmetry of the molecular packing into a layer.

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Dielectric and nonlinear optical properties in low molecular and polymericc ferroelectric liquid crystals (FLCs) which have a nitro group in the core part of their molecular structure have been studied. Low molecular FLC, MS1 shows a very large spontaneous polarization (Ps) and an intense second harmonic generation (SHG) , which is attributed to the nitro group introduced in the core part. The liquid crystalline properties, Ps and optical nonlinearity strongly depend on the position of the nitro substituent in the molecular structure.

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New transverse electro-optical effects in ferroelectric SmC^* liquid crystals (FLC) are suggested for a gray scale spatial light modulators. These effects are observed in transverse geometry with crossed light propagation direction and direction of electrical field. FLC is aligned homeotropically in this case. Suggested effects obtain quasi-linear (without threshold) dependence of light transmission upon applied electrical field , even in very low electrical fields (less than 0.1 V/μm,). Contrast ratio is high and uniform (it can be more than 100:1 ).

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The successive phase transitions in ferro- and antiferro-electric smetics have been discussed on the bases of the ANNNI model with the third next nearest neighbour interaction. Here, the nearest neighbour interacting modeh with variables indicating the sense of the molecular long axis is introduced to certify that model. By taking the summation over all states of these variables in the partition function the system is transformed into the effective Hamiltonian with long range interactions and many body forces. In the minimal theory where the range of the interaction is taken into account up to the third nearest neighbour, the assumptions appearing in the above ANNNI model are justified. In the intermediate phases excerpt for SmC^* and SmC_A^* the ordering of the molecular sense is shown to be induced by the bias due to the order of layer stacking.

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In the course of certification of the ANNNI model with the third nearest neighbour interaction J₃ applied to the successive phase transitions occurring in the ferroelectric smectics the four body force J_4b is shown to be induced. The effects of J₃ and J_4b are studied and J_4b is shown not to be essential in the high temperature region in the ordered phases, which is applicable to the phase transitions concerned here. That means the first Hamiltonian is the effective Hamiltonian for these phenomena. The mesophases are studied where ferrielecric phase named as FI_L is suggested to have a wave number 2/5, and those FI_H and FI are assume to have the ones 2/7 and 1/5, respectively. The reasonwhy the mesophase FI is observed scarcely is also discussed on the basis of the phase diagrams.

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Our previous theoretical model has revealed that the molecular head-tail difference is one of important origins of the successive phase transitions of chiral smectics. In the model, we assume that the tilts of molecules in smectic layers are restricted as they are parallel to one plane which includes the layer normal. In the present study, we generalize the model as it can describe the freedoms of azimuthal angle and polar angle of molecular tilts and discuss behavior of the phase transitions more generally.

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We have observed the segmental order parameter of partially deuterated MHPOBC by ²H-NMR spectroscopy in liquid crystalline phases in order to investigate the molecular conformation. We discuss the orientaional order parameter in an antiferroelectric liquid crystal and its influence on the appearance of antiferroelectric liquid crystal.

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The crystallinity of nylon which has monoclinic structure can be centrolled by annealing condition. We found that the higher crystalline layer produced the better aligned cell. There were no significant differences in pretilt angles of the cells with crystalline, midstate crystalline, and amorphous layers. But in cone angle and contrast ratio the cell with higher crystalline layer showed better result.

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The memory capability of the surface stabilized ferroelectric liquid crystal display in conjunction with the thickness of molecular alignment layer has been investigated. We clarified the thickness effect on the each part of polarization switching behavior. The thickness effect is interpreted by the space charge transportation in terms of polarization switchings of the ferroelectric liquid crystals. The improved memory capability due to the layer thickness research enables us to fabricate a high contrast ratio ferroelectric liquid crystal display with the XGA pixel.

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We have found a new analog gray-scale technique for ferroelectric liquid crystal (FLC) displays ¹⁾. The new technique involves the micro-domain texture, and the addition of nanometer-scale particles into the FLC mixture enables a wide distribution of threshold voltages within one pixel. This threshold-voltage broadening was found to be caused by an increase in the distribution of the smectic-layer tilt angles ³⁾. The hysteresis in the voltage-transmittance curve is one of the crucial problems for realizing analog gray-scale displays. We report that the causes of the hysteresis are the relaxation of the polarization in the alignment layers brought about by the spontaneous polarization and the instability of the memory effect. In order to accelerate the depolarization in the alignment layers, we have increased the conductivity and controlled frame rates to clarify the relationship between the memory stability and the hysteresis.

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We have investigated mechanical vibration in antiferroelectric liquid crystal display panel under applied electric field. We found that the frequencies of panel vibration are the frequency of applied field and its harmonics. We also found that the natural frequency determines the shape panel transformation. We suppose that Maxwell's stress, caused by the applied field variance, vibrates the glass plats of the panel.

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Novel antiferroelectric liquid crystals of tetralin derivatives have been prepared, and their phase transition temperatures and electro-optical properties were investigated. The introduction of a double bond into tetralin skeleton showed expanded antiferroelectric phase, whereas the fluorinated tetrarin derivative showed monotropic antiferroelecrtic phase. The relationships between molecular structure and electro-optical property are discussed.

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In order to investigate the conformation of the chiral alkyl chain by polarized ir spectroscopy, we synthesized achiral chain deuterated MHPOBC-d₂₅, TFMHPOBC-d₂₅ and TFMHPNCBC-d₂₇. In TFMHPOBC-d₂₅ and TFMHPNCBC-d₂₇gt;, the carbon of the carbonyl group near the chiral center was also enriched by ¹³C, in order to seperate its ir peak wxth that assugned to the core carbonyl group.

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We have synthesized two deuterated MHPOBCs, MHPOBC-d₃ with the methyl group connecting to the chiral center deuterated, and MHPOBC-d₄₃, all deuterated but the methyl group near the chiral part. The polarization angle dependence of FT-IR shows that the symmetric and asymmetric stretchings of methyl group are in-phase with those of phenyl rings in SA and electrically unwound SC^* phases.

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