First, the quartz glass substrate (Suprasil, Heraeus) is covered with a 70 nm thick spacer layer by spin-coating. A solidifiable photopolymer, PC403 (JCR, Japan), is used. A prebaking process is first carried out to remove the solvent from the polymer (increase of the baking temperature from 90 °C to 130 °C). A sufficiently long bake at a higher temperature (30 min at 180 °C) further hardens the layer. Next the three particle L-shape layer (dot diameter 200 nm, surface-to-surface distance 20 nm) and alignment markers are defined in resist (double layer PMMA, Allresist) using electron-beam lithography (Raith e_Line). The substrate is then covered with a 2 nm Cr adhesion layer and a 40 nm gold film using thermal evaporation followed by a lift-off procedure. Subsequently, a 70 nm thick spacer layer of PC403 is applied. Afterwards the substrate is coated once more with PMMA resist. Computercontrolled alignment at the sub-10 nm level using the gold alignment markers is applied to ensure the accurate positioning of the upper dot layer. Metal evaporation, lift off, and final planarization are repeated. All samples have a total area of 30 µm ×30 µm. All scanning electron microscope (SEM) images are taken with a Hitachi S-4800 scanning electron microscope. Optical characterisationThe spectra are measured using a Fourier-transform infrared spectrometer (Bruker Vertex 80, tungsten lamp), equipped with an infrared microscope (Bruker Hyperion). The incident light is focused with a Cassegrain objective with numerical aperture N = 0.4, and the transmitted intensities are detected with Si and InGaAs diodes. The incident polarization is set with an infrared polarizer and a broadband (700 nm -2500 nm) infrared quarterwaveplate (B. Halle Nachfl., Berlin). The measured spectra are normalized with respect to the substrate.

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A new method is developed for the determination of Saupe's order parameters S* and D* from I.R. or U.V. spectra and the temperature dependence of their degree of anisotropy R. This method can be applied to molecules with one uniformly polarized band and another band of mixed polarization if all bands concerned are polarized in the same plane. For that a relation D* = f ( S * ) between the order parameters as a function of temperature is necessary, which can be obtained from the lines of constant entropy in the order triangle. These isentropics are calculated from the orientational distribution function of the ordered system. The resulting function D* = f ( S * ) is equal to that of the mean field theory given by Luckhurst et al., but can be derived here in a very easy way. The method is applied to diaminoanthraquinones with a point symmetry C,, .

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