Why are fewer atoms counted in a nanometric volume than experimental and analytical?

Geometry, Fields and Transportation
1

Dear experts!

I was tested how many atoms are in per 3 nm gold nanoparticle and compared it with some experimental work. In Geant4.10.07, it was counted about 219 gold atoms by via the function “GetTotNbOfAtomsPerVolume()” , whereas there were about 479 gold atoms per nanoparticles in the experimental work.

The material was considered as the Au197 isotope with a 19.32 g/cm³ density.

In this case, is it normal to calculate and validate for the radio-enhancement effect?

Best wishes,
Togtokhtur

2

GetTotNbOfAtomsPerVolume() gives ~59 atoms per nm3 (see below).
You can easily double check this value by a simple computation by hand.

gold.out.txt (454 Bytes)