[CPMD-list] HELP: Explaination to manual 9.5.2

[liuzhim]

Hi, every body:
   I have a question to the manual for CPMD, and hope somebody may give help.
    I want to handle some finete temperature simulations via CPMD.  All the examles were tried. Recently, when I read the manual carefully, the sentence  "geometry optimizations and molecular dynamics simulations can only be performed after an electronic spectra calculation" in section 9.5.2 makes me much confused. Does it mean that I should calculate the electronic spectra even though I just want to perform a dynamical simulation  to investigate the mechanical or thermal properties for ions while the electronic properties are neglected? If I do not do the spectra work, what will occur to the results?
                                                        Z. M. Liu from , Changchun, P.R.C 
                                                         Dec. 16, 2007
                                                        liuzhim at mail.jl.cn
                                                                 .