When laser ablation pressure has a significant influence particle formation in the first place in the liquid medium than in the gas or in vacuo. This is due to the fact that the liquid environment formed a significant restriction on the distribution of

plasma cloud, which in turn leads to a higher temperature, density and pressure. Furthermore, at the liquid-section of the plasma takes place heating and evaporation of the liquid, which leads to additional chemical reactions.

Liang C. и др. Synthesis, characterization, and phase stability of ultrafine

TiO2 nanoparticles by pulsed laser ablation in liquid media // J. Mater. Res. 2004.

Т. 19. № 05. С. 1551–1557

Best regards.

Dear Yuri Mirgorod,

Thank you very much for details.

I'm looking for a relationship between Absorption peak (position , FWHM and intensity) and thickness of shell for core-shall nanoparticals .

Regards

Ghaleb

Dear Dr. Ghaleb:

Тhe size of the core and the shell of nanoparticles can be determined by SAXS. The larger the cross-section of the electron density of the core and shell, the greater the intensity of the X-ray scattering.

Best regards.

From your query it seems the Ag is Core and Au is Shell in your core-shell system. I guess fluorescence would be helpful and it will be sensitive enough to tell you about thickness of Au Shell. Gold nanoparticles are fluorescent. Have a look at this,

https://www.researchgate.net/publication/233731536_Physical_Properties_of_Different_Gold_Nanoparticles_Ultraviolet-Visibleand_Fluorescence_Measurements

Article Physical Properties of Different Gold Nanoparticles: Ultravi...

Dear , Yuri Mirgorod , Gaser Nagah Abdelrasoul  , Atindra D Shukla ,

  Thank you so much for all explanations .Very good clarification .

if there are any more theoretical calculations of shell thickness from FWHM of Absorption peak? or papers in filed .

Thanks

Best Regards

Ghaleb 

Dear prof. Ghaleb

The article on the link blow contains trial for estimating the function of shell thickness Vs. peak energy shift using the Gaussian-Lorentzian mixed function.   

Best regards

"Enhanced Electronic Properties of Pt@Ag Heterostructured Nanoparticles"

 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3715221/

still under publication "Multimodal Iron-oxide/Gold  Nanoprobes for Non-invasive Radiofrequency Hyperthermia and Magnetic Imaging"

Synthesis of nanoshell and/or composite nanoparticles by reduction of Au3+ on the surface of Fe oxide using the seeding procedure. Choice of the reduction technique, time, and concentration determines the size and shape of the nanocomposites generated. Morphological control is a useful tool to engineer the optical properties of materials. Gold has a much higher surface energy than magnetite, and so it will not deposit evenly over the surfaces. Attaching gold seeds creates nucleation sites for further metal deposition, and also alters the effective surface energy of the oxide particle allowing an even metal layer to be deposited. After this the seeded particles can grow to full core–shell structure by using glycerin as a mild reducing agent.

Dear Mohammed Hussein j. H. Al'Atia 

Dear Alsayed A M Elsherbini 

Thank you very much for all explanations .

With Best Regards

Ghaleb