BornAgain

• Change of 2D lattice length in GUI should lead to TotalSurfaceDensity recalculation in ParticleLayoutItem
• Also users are confused by default total surface density 1.0 - they think that particles are covering whole surface and overlap.

From mail of Odarchenko Yaroslav

It says that ParticleSurfaceDensity is number of particles per square nanometer  http://apps.jcns.fz-juelich.de/doxy/BornAgain/classParticleLayout.html#ad226b2998b390c39872bf54855090b07

If you look into the BornAgain GUI and select “Core shell particle” from the standard samples the ParticleSurfaceDensity is set to 1 by default (attached exported file).

Does it mean that particles are covering fully the surface?

If yes, then why this value is fixed to 0.00288675134595 and cannot be changed by user for the standard sample “Interference 2D paracrystal” (attached exported file). Also it does not change by modifying latticelength parameter that will change the number of particles per unit of area.