%0 Conference Paper
%F Oral 
%T Self-assembling through H bonds in urea and thiourea based bridged silsesquioxanes
%+ Laboratoire Charles Coulomb (L2C)
%+ Department of Physics and CICECO, University of Aveiro,
%+ University of the Sunshine Coast (USC)
%+ Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM)
%+ Optique et Matériaux (NEEL - OPTIMA)
%+ Department of Physics and CICECO, University of Aveiro
%A Le Parc, Rozenn
%A Freitas, Vânia
%A Cojocariu, Ana M.
%A Wong Chi Man, Michel
%A Cattoën, Xavier
%A Ferreira, Rute A. S.
%A Carlos, Luis D.
%A Bartlett, John R.
%A Bantignies, Jean-Louis
%F Invité
%< sans comité de lecture
%Z L2C:16-325
%B The 2nd International Conference on NanoMaterials for Health, Energy and the Environment
%C Flic en Flac, Mauritius
%8 2016-09-07
%D 2016
%Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Conference papers
%X Associations of organic and inorganic molecules involving non covalent and covalent interactions participate to a wide range of structures found in nature. Bridged silsesquioxanes (BS) can be designed with organic units selected to drive self-organization into a solid network. Therefore new hybrids functional materials with controlled morphologies can be synthesized. In particular urea groups, thanks to their ability to self-assemble though H bonds, have been incorporated in BS within the organic subunits (figure 1, UU). Depending on kinetics of the sol gel reaction, hybrid materials bridged by urea groups exhibiting a variety of textures and morphologies were synthetized. Considering the bridging group as a key element for the control of the assembly formed hybrids materials where thiourea groups have also been synthesized (Figure 1, UU or TT). As a matter of fact thiourea groups are also known to link them self via H bonds, but with geometry and strengths that can differ from urea links. Vibrational spectroscopy is used here to explore the self-organization mechanisms involved in the formation of urea bridged and thiourea bridged silsequioxanes. The influence of H-bonding strength and the self-organization properties of the urea and thiourea bridged organic substructures are explored through infra-red spectroscopy coupled with DFT calculations. Some particular vibrations such as amides and thio-amides vibrations are often considered as signatures of H bond strength. The thermal dependence dynamics of such signatures is studied as an indicator of the bond properties. Finally, in-situ high pressure vibrational measurements demonstrate the role of supramolecular interactions on the mechanical response of hybrid materials to high pressure.
%G English
%L hal-01909521
%U https://hal.science/hal-01909521
%~ UGA
%~ CNRS
%~ ENSC-MONTPELLIER
%~ INPG
%~ NEEL
%~ ICG
%~ L2C
%~ INC-CNRS
%~ NEEL-OPTIMA
%~ MIPS
%~ CHIMIE
%~ UNIV-MONTPELLIER
%~ UGA-COMUE
%~ UM-2015-2021