Concepts of BornAgain Motivations BornAgain software: simulating and fitting grazing-incidence small-angle scattering from assemblies of nanoparticles C. Durniak , M. Ganeva, P. Pospelov, W. Van Herck, J. Wuttke Jülich Centre for Neutron Science (JCNS) at MLZ, Forschungszentrum Jülich GmbH, Garching, Germany BornAgain: - open source software package to simulate and fit small angle scattering at grazing incidence. - provides a generic framework for modeling multilayer samples with smooth or rough interfaces and with various types of embedded nanoparticles. Conclusion [1] G. Renaud, R. Lazzari, F. Leroy, Probing surface and interface morphology with Grazing Incidence Small Angle X- Ray Scattering, Surface Science Reports 64, 255 (2009). [2] http://bornagainproject.org References Scattering intensity = function of particles (shapes, sizes), distributions of particles, layers of materials. Examples Contact: [email protected] Phone: +49.89.289.11678 ✓ Support for multilayers ✓ Interface roughness correlation ✓ Magnetic materials ✓ Multiple type of nanoparticles (~20 shapes) Particles ✓ Lattices ✓ Disordered systems ✓ Short-range order distribution ✓ Size-spacing distribution ✓ Deposited / embedded particles Positions of particles ✓ Divergence of the input beam (wavelength, angles…) following different distributions ✓ Polarized neutrons ✓ Off specular scattering ✓ 2D detector Beam / detector ✓ Simulation / Fitting ✓ Python scripting or Graphical User Interface Use of BornAgain ✓ Particles with inner structures ✓ Assemblies of particles ✓ Size distribution Geometry of a GISAS experiment Ag cuboctahedral particles distributed along an hexagonal lattice, deposited on Al 2 O 3 , Si layers. Random distribution of Au truncated spheres and spheroids with Cu spherical cores deposited on SiO 2 and Si layers. Hexagonal lattice Core-shell Grazing incidence small angle scattering (GISAS): - surface sensitive, non destructive technique - large area coverage statistical information - tunable depth probe by changing input angle - use of X-ray or neutrons to scan different properties - characterisation of deposited or embedded nanoparticles, layered materials [1] Challenging data analysis in reciprocal space: - multiple reflections at interfaces due to small incident angle - measurement of intensity loss of information modeling the sample + fit to match experiments BornAgain software to simulate and fit GISAS data [2] Solution Layers Multilayered structure with roughness Si SiO 2 Au Cu Planar layouts of particles Deposited or embedded particles in layers Input beam with wavelength divergence Ag Si Al 2 O 3