Query Regarding Silver and Zinc Oxide Nanoparticle

[zaved]

Dear Sir

I have constructed Silver Nanoparticle (NP) and Zinc Oxide nanoparticle of diameter 4nm ( cluster radius 20 Å each) using VNL 2016.3.

However when I have checked the radius of gyration (Rg) for both the nanoparticle, it was showing less the half of the diameter.
For Silver NP, the Rg is 1.78 nm approx and for ZnO NP, it is 1.37 nm approx., which should have been 2nm approx for both the strucutres.

Can you kindly comment on the issue, why the Rg value is showing lesser for both the structures?

Thank You

Regards
Zaved Hazarika
PhD Student
Dept of MBBT
Tezpur University
Assam
India

[Ulrik G. Vej-Hansen]

The radius as specified in the nanoparticle builder is simply the maximum distance that is used in the Wulff construction in any direction. It is always a bit ambiguous how to define the diameter of a non-spherical nanoparticle, so I am not at all surprised that different methods of defining it will give different results.