This paper describes the first examples of heteropolynuclear metallomesogens that contain both a transition metal ion and a trivalent lanthanide ion. Adducts were formed between a mesomorphic [Cu(salen)] complex (salen 2,2'-N,N'-bis(salicylidene)ethylenediamine) with six terminal tetradecyloxy chains and a lanthanide nitrate (Ln La, Gd). Different stoichiometries were found, depending on the lanthanide ion: a trinuclear copper ± lanthanum ± copper complex [La-(NO 3 ) 3 {Cu(salen)} 2 ] and a binuclear copper-gadolinium complex [Gd(NO 3 ) 3 Cu-(salen)]. The compounds exhibit a hexagonal columnar mesophase (Col H ) over a wide temperature-range with rather low melting temperatures. Although the clearing point could be observed for the parent [Cu(salen)] complex, the mixed f ± d complexes decomposed in the hightemperature part of the mesomorphic domain before clearing. On the basis of X-ray diffraction measurements and molecular modelling, a structural model for the mesophase of the metal complexes is proposed.

Parameters affecting the quality of TXRF measurements in solutions were studied.  Concentrations of analyte and standard should be similar for good recovery rates.  Internal standard and analyte must have similar X-ray fluorescence energies.  Recommendations for measurement of metals in solutions by TXRF are presented.

Lanthanide complexes of the Schiff base ligand 4-dodecyloxy-N-hexa-decyl-2-hydroxybenzaldimine and with perfluorinated alkyl sulfate counterions were synthesised. All of the metal complexes show a smectic A mesophase. The viscosity of this mesophase is much lower than that of analogous compounds with nitrate or alkyl sulfate counterions. The behaviour of these new highly anisotropic molecular magnetic materials was studied using high-temperature X-ray measurements in an external magnetic field and temperature-dependent magnetic susceptibility measurements. The m eff-versus-temperature curve is more comparable with those expected for nematic phases than for smectic phases. The luminescence spectrum of a Eu III compound shows that the values of the second rank crystal field parameters are very large. The huge magnetic anisotropy can be related to this strong crystal-field perturbation.

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