Lyotropic La-containing lamellar liquid crystals: phase behaviour, thermal and structural propertiesElectronic supplementary information (ESI) available: The optimized structure of the C12EO4/La(NO3)3·6H2O complex and the details of the transverse relaxation experiment. See DOI: 10.1039/c5sm01371b

This paper provides the results of POM, DSC and XRPD methods characterizing the liquid crystalline behaviour, thermal properties and structural parameters of lyotropic systems based on a nonionic surfactant and lanthanum nitrate (La 3+ ). The systems based on tetraethylene glycol monododecyl ether (C 12 EO 4 ) and lanthanum nitrate have been demonstrated to form a lamellar phase. The concentration and temperature ranges of the existence of mesophases as well as thermodynamic parameters of phase transitions have been estimated. The structural parameters of the lamellar phase of the C 12 EO 4 /La 3+ /water systems have been determined using X-ray diffraction. The model of molecular packing in lamellar lanthanide-containing lyotropic mesophases was proposed for the observed patterns of structural parameters obtained at various water contents. NMR 1 H with a pulsed magnetic field gradient has been used to characterize molecular motions in the C 12 EO 4 /La 3+ /H 2 O systems with different water contents. The phase behavior and regularities of structural properties of lanthanum-containing lyotropic liquid crystals in aqua solution using a combination of physical chemistry methods and quantum chemical simulations are explored.