Hello Ari,

I don't quite understand your question. Are you going to simulate the optical response of your metallic nanoparticles under SPR excitation? I have two related papers talking about the Fe and Co nanoparticles under localized surface plasmon resonance excitation in my homepage. I hope they are helpful.

https://www.researchgate.net/profile/Lei_Wang62/publications/

the basic plasmon resonance of nanoparticle is a well covered topic in many of the introductory texts. Have you tried Stefan Maier's book or the Novotny and Hecht text. Also Zayats has big review article of plasmonics where the localized surface plasmon modes are discussed.

thanks Lei and Josh I already read the Maeier´s book and it helped me so much!!

To define the dielectric function of metals , a good reference for many metals on Broadband from about 6 to 0.2eV is:

Rakic, A. D., Djurisic, A. B., Elazar, J. M. and Majewski, M. L., Optical properties of metallic films for vertical-cavity optoelectronic devices, Applied Optics,Vol. 37, No. 22 (1998) pp. 5271-5283.

Dear Ari, you also have the book of Bohren and Huffman "Absorption and Scattering of Light by Small Particles".