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CPMD computational code

Hutter, J. et al. Computer code CPMD, version 3.11 (copyright IBM Corp. 1990-2008 copyright fiir Festkorperforschung Stuttgart, Germany, 1997-2001), http //www.cpmd.org/. [Pg.859]

Although the preferred method of calculating a spectrum is to perform an ab initio calculation on an extended solid, extracting frequencies and displacements across the Brillouin zone, on a fine A-grid, this approach can be computationally very expensive. In plane wave codes like CASTEP [18], CPMD [19], TWSCF [20], VASP [21], ABINIT [22], and some others, the number of plane waves that are taken into consideration, the selected correlation fimctional and the choice of pseudopotential will all have an impact on the quality of the calculations. Some codes (e.g. ABINIT) alleviate the problem by permitting frozen phonon calculations at the symmetry zone boundary, i.e. (0,0,0), (l/2,0,0), (l/2,l/2,0) and (l/2,l/2,l/2) and so determine the dynamical matrix at these points. The code then interpolates values of the d3mamical matrix for all the points within the Brillouin zone and uses these to calculate the solution to the vibrational problem inside the zone. [Pg.167]


See other pages where CPMD computational code is mentioned: [Pg.162]    [Pg.121]    [Pg.80]    [Pg.306]    [Pg.161]    [Pg.20]    [Pg.478]    [Pg.87]    [Pg.3256]   
See also in sourсe #XX -- [ Pg.167 ]




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