### Core-and-shell nanoparticles

Scattering from cuboidal core-shell particles.

• The sample is made of core-shell particles whose outer and inner shells are boxes with dimensions $L_1 = W_1 = 16$ nm, $H_1 = 8$ nm and $L_2 = W_2 = 12$ nm, $H_2 = 7$ nm, respectively, where $L_i$, $W_i$ and $H_i$ are the length, width and height of box $i$.
• The smaller box is positioned so that the centres of the bottom faces of both particles coincide.
• The simulation is run using the Born approximation. There is no substrate and no interference between the different scattered beams.
• The planar distribution of the particles is diluted and random.
• The incident wavelength is equal to $1$ $\unicode{x212B}$.
• The incident angles are $\alpha_i = 0.2 ^{\circ}$ and $\varphi_i = 0^{\circ}$.
  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61  #!/usr/bin/env python3 """ Core shell nanoparticles """ import bornagain as ba from bornagain import deg, nm def get_sample(): """ Returns a sample with box-shaped core-shell particles on a substrate. """ # Define materials material_Core = ba.HomogeneousMaterial("Core", 6e-05, 2e-08) material_Shell = ba.HomogeneousMaterial("Shell", 0.0001, 2e-08) material_Vacuum = ba.HomogeneousMaterial("Vacuum", 0, 0) # Define form factors ff_1 = ba.FormFactorBox(12*nm, 12*nm, 7*nm) ff_2 = ba.FormFactorBox(16*nm, 16*nm, 8*nm) # Define particles particle_1 = ba.Particle(material_Core, ff_1) particle_2 = ba.Particle(material_Shell, ff_2) # Define core shell particles particle_3 = ba.ParticleCoreShell(particle_2, particle_1) # Define interference functions iff = ba.InterferenceFunctionNone() # Define particle layouts layout = ba.ParticleLayout() layout.addParticle(particle_3) layout.setInterferenceFunction(iff) layout.setTotalParticleSurfaceDensity(0.01) # Define layers layer = ba.Layer(material_Vacuum) layer.addLayout(layout) # Define sample sample = ba.MultiLayer() sample.addLayer(layer) return sample def get_simulation(sample): beam = ba.Beam(1, 0.1*nm, ba.Direction(0.2*deg, 0)) detector = ba.SphericalDetector(200, 2*deg, 0, 1*deg) simulation = ba.GISASSimulation(beam, sample, detector) return simulation if __name__ == '__main__': import ba_plot sample = get_sample() simulation = get_simulation(sample) ba_plot.run_and_plot(simulation) 
CoreShellNanoparticles.py