Comment on "Silver nanoparticle array structures that produce remarkably   narrow plasmon lineshapes" [J. Chem. Phys. 120, 10871 (2004)]
  In this Comment I discuss two incorrect statements which were made in the paper "Silver nanoparticle array structures that produce remarkably narrow plasmon line shapes" [J. Chem. Phys.120, 10871 (2004)] by Zou, Janel, and Schatz (ZJS). The first statement is about the use of quasistatic approximation in my earlier work on the similar subject, and the second statement concerns the possibility of exact cancellation of radiative relaxation in periodical chains of nanoparticles. The relationship between the quasistatic approximation, the dipole approximation, and the approximation due to Doyle [Phys. Rev. B39, 9852 (1989)] which was used by ZJS is clarified. It is shown that the exact cancellation of radiative relaxation cannot take place in the particular geometry considered by ZJS. 
Vadim A. Markel