Complexes of 2,3-dimethoxybenzoates of Co(II), Ni(II) and Cu(II) have been synthesized as hydrated or anhydrous polycrystalline solids and characterized by elemental analysis, IR, FIR and electronic spectroscopy, magnetic studies and X-ray diffraction measurements. The carboxylate groups bind as monodentate or symmetrical, bidentate chelating and bridging ligands. The thermal stabilities were determined in air. When heated they dehydrate to form anhydrous salts which are decomposed to the oxides of the respective metals. The magnetic susceptibilities of the complexes were measured over the range 77?300 K and the magnetic moments were calculated. The results show that the complexes of Ni(II) and Co(II) are high-spin complexes and that of Cu(II) forms a dimer.

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The 4-pentylphenyl-4'-pentox thiobenzoate (5S5), C,,H,,O,S, cr stallizes in the monoclinic system: space group P2,/c, a = 19.817 (2) 1, b = 5.585 (1) A, c = 20.238 (2) = 104.792 (8)', z = 4. The structure was solved by direct methods and refined to the final R=0.065, for 3415 observed reflections. The pentoxythiobezoate moiety is nearly planer. Molecular rows form an interclated structure. C-H ... 0 type short intermolecular contacts were found.

This article reports on the new results on phase transitions, mesomorphic and electro-optical properties of new equimolecular mixture of calamitic and bent-core thiobenzoates. Two following liquid crystals were the components of the binary mixture: (S)-(+)-4-(1-methylheptyloxy)biphenyl 4 ′ -octylthiobenzoate (MHOBS8) having rode-like, calamitic-chiral molecules possessing among others ferroelectric smectic C (SmC * ) and bis [4-(4 ′ -octylphenylthiocarbonyl)phenyl] isophtalates from a homologous series of banana-shaped thioesters, referred to as IFOS8, where n = 8 denoted the number of carbon atoms in terminal alkyl chains in both mesogens, synthesized by us. The IFOS8 compound has two enantiotropic phases: B2 with antiferroelectric order and B6. The mesomorphic properties were investigated by means of three complementary methods: dierential scanning calorimetry, polarized light optical microscopy, and transmitted light intensity. Electro-optical measurements were also carried out.

A method of determining the set of four order parameters S , D , P , and C for a ferroelectric liquid crystal, using complementary results for different sample geometries, is presented. IR measurements have been performed for homeotropic, planar heterogeneous and, planar homogenous sample geometries. Orientational order parameters were determined in two frames of reference to obtain complete information on molecular arrangement. Results for the D , P , and C parameters indicate the importance of both the intrinsic and extrinsic biaxialities. The molecular rotation around the long molecular axis is not free, and the carbonyl dipole and plane of the central phenyl ring are oriented close to the tilt plane. It has been found that transition dipole moments show significant correlations, antiparallel for longitudinal dipoles and parallel for transversal ones.