MOLPRO

34 PROPERTIES AND EXPECTATION VALUES 265
34.6.1 Example
***,ar2
geometry={ar1;ar2,ar1,r}
r=2.5 ang
{hf;
expec,rel,darwin,massv}
e_nrel=energy
show,massv,darwin,erel
dkroll=1
hf;
e_dk=energy
show,massv,darwin,erel
show,e_dk-e_nrel
!geometry definition
!bond distance
!non-relativisitic scf calculation
!compute relativistic correction using Cowan-Griffin operator
!save non-relativistic energy in variable enrel
!show individual contribution and their sum
!use douglas-kroll one-electron integrals
!relativistic scf calculation
!save relativistic scf energy in variable e_dk.
!show mass-velocity and darwin contributions and their sum
!show relativistic correction using Douglas-Kroll
http://www.molpro.net/info/current/examples/ar2_rel.com
34.7 CUBE — dump density or orbital values
CUBE,filename,iflag,n 1 ,n 2 ,n 3
calls a module which dumps the values of various properties on a spatial parallelopipedal grid
to an external file. The purpose is to allow plotting of orbitals, densities and other quantities by
external programs. The format of the file is intended to be the same as that produced by other
programs.
filename
iflag
n 1 ,n 2 ,n 3
is the unix path name of the file to be written, and its specification is
mandatory.
If iflag is negative (default), a formatted file will be written, otherwise
unformatted fortran i/o will be used.
specify the number of grid points in each of three dimensions. If not
specified, sensible defaults are chosen.
By default, the last density computed is evaluated on the grid, and written to filename. This
behaviour can be modified by one or more of the following subcommands.
34.7.1 STEP — setting the point spacing
STEP,[stepx],[stepy], [stepz]
stepx,stepy, stepz specify the point spacing in each of three axis directions. By default, the value
of stepx,stepy, stepz is determinated by the number of grid points, the bragg radii of the atoms,
and some related parameters.
34.7.2 DENSITY — source of density
DENSITY,[density-source]
GRADIENT,[density-source]
LAPLACIAN,[density-source]