Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.
DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.
The present study reports on the synthesis of nanocrystalline (K-x,Na1-x)NbO3 powders prepared via microemulsion mediated hydrolytic decomposition of mixed alkoxide solutions. Compositions with different K/Na ratios ranging between the two end members KNbO ...
The three-dimensionally modulated incommensurate crystal structure of lazurite from the Baikal region was determined for the first time. The structure was solved within the cubic system with the unit-cell parameter a(cub) = 9.077(1) Angstrom and the (3+2)- ...
Using the Landau-Ginzburg-Devonshire approach, the longitudinal piezoelectric coefficient in an arbitrary direction, d(33)()(theta), was calculated as a function of temperature in tetragonal BaTiO3 crystals. The direction along which d(33)()(theta) is ma ...
The orientation dependence of the longitudinal piezoelectric coefficient, d(33)(*), is investigated as a function of temperature in BaTiO3 and PbTiO3 crystals using the Landau-Ginsburg-Devonshire theory. We show that a presence of the ferroelectric-ferroel ...
The HH and HV Raman spectra of vitreous silica are calculated from first principles for a model structure consisting of a disordered network of corner-sharing tetrahedra, for which the vibrational properties were obtained previously. We analyse the contrib ...
To calculate the Raman spectrum of vitreous silica, we use a model structure consisting of a disordered network of cornersharing tetrahedra, for which the vibrational frequencies and eigenmodes were obtained previously by first principles. The Raman cross- ...
Using a first-principles density functional approach, we calculate the first-order Raman intensities of alpha -quartz. The dynamical charge tensors, vibrational frequencies and eigenmodes, and polarizability tensors are obtained within a perturbational app ...
Using a first-principles approach, we study the vibrational properties of vitreous SiO2 which are measured in neutron-scattering experiments. We adopt a model structure consisting of corner-sharing tetrahedra, which was previously generated using first-pri ...
Recent developments in Raman spectroscopy at high pressure, high temperature and combined high pressure and variable temperature are presented. The instrumental and technical aspects of Raman spectroscopy, and coupling of diamond anvil cells and miniature ...
N-Salicylideneaniline (SA), C13H11NO, belongs to the large family of aromatic Schiff bases. It is of particular importance owing to its reversible photoreactivity. SA forms two photochromic polymorphs, both with two non-coplanar benzene rings. In addition, ...
