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Acta Cryst. (2014). A70, C621
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Small molecules, such as urea, thiourea, perhydrotriphenylene can be co-crystallised with long-chain hydrocarbon molecules to form inclusion compounds. The guest chains are confined to narrow, approximately cylindrical, channels created by the host small-molecule lattice. The stoichiometry and the conformations of the chains included inside the channels are function of internal interactions such as intra-chain interaction, but also of overall co-operative properties of the resulting three dimensionally ordered single crystal. These intergrowth compounds may form incommensurate composite crystals. A prototype example of such uniaxial intergrowth aperiodic crystals is n-alkane (CnH2n+2)/urea (CO(NH2)2). In these supra-molecular systems, urea molecules are connected by H-bonds and form helical ribbons, which repeat every six urea molecules to form a series of linear, hexagonal tunnels that can accommodate linear alkanes. Because the channels (~0.53 nm) are larger than the hydrocarbon chains, guests are held loosely and can undergo substantial motions. A significant amount of diffuse scattering of the first and second kinds can be depicted in scattering experiments, static or dynamic. These materials undergo a large variety of continuous or weakly first order structural phase transitions when changing the alkane molecule length and giving place to large pre-transitional effects. The talk will give an overview of the diffuse scattering in these compounds and will focus on connection with aperiodicity.

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Acta Cryst. (2014). A70, C1279
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Modern crystallography makes intense use of large scale facilities: neutron reactors, synchrotron sources, free electron lasers, where sources, optics and detectors allow for a wide range of possible experiments putting forwards the limits of the analysis of the structure and dynamics of matter and materials. Giving the large scale facilities a major role in the teaching of crystallography and material science, allowing for intense practice, requires to gather different skills which is more often done through summer school or intensive programs at PhD or junior scientist level. The Erasmus Mundus Master Course MaMaSELF (Master in Material Science Exploring Large Scale Facilities) is a unique European master program focused on the use of large scale facilities to investigate intimate nature of matter and materials where the five consortium higher education institutions (University of Rennes 1, France; Technische Universität München and Ludwig Maximilian University in München, Germany; University of Torino, Italy and University of Montpellier 2, France) have managed, together with Large Scale Facilities partners (ESRF, ILL, FRMII, DESY, LLB, SOLEIL, PSI) and third country partners spread out all over the world (Brazil, India, Japan, Russia, Switzerland , USA), to offer to the students a two years program at the master level including large amount of crystallography and spectroscopy teaching and an intensive summer-school totally dedicated to large scale facilities and including a large proportion of lessons and labs taught by experts, as well as many internship and master thesis opportunities at the large scale facilities.
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