[Pw_forum] inqure about the theory of infrared spectrum calculation

[Paolo Giannozzi]

xu yuehua wrote:

> and is that theory used in PWSCF code?   

http://www.springer.com/physics/book/978-1-4020-3287-5
go to 'Sample pages', download the file. It contains a brief
introduction to density-fgunctional perturbation theory,
including some essential info on how to calculate IR cross
sections

P.
-- 
Paolo Giannozzi, Democritos and University of Udine, Italy