[molpro-user] Help for LTTICE command!

[Tsuneo Hirano]

Dear MOLPRO developers and users,

I would like to calculate the effect of a point charge using the 
LATTICE command.
However, the manuals for MOLPRO 2006 and 2008 do not provide 
sufficient explanation for "LATTICE" command.

For example, the test input file, lattice.test, in the directory 
"testjobs" included in the MOLPRO source codes, contains several 
options that are not provided in the manual:
     method=argos, method=potint, method=xfdint, and unit=ang,
in such a way as,
     lattice,method=potint,unit=ang.
"Unit=ang" may mean that the coordinates are given in Angstrom.  But, 
what do the other options for the method mean?

The following is my input for the case where one point charge of -1.0 
is placed on the z-axis at 2.0 Angstrom from the oxygen of water.  Is 
this input correct ?
Differently from the statement in the manual (it says that 
coordinates should be in Angstrom), the job using MOLPRO 2006, and 
2008 also, was aborted when I took out “unit=ang” from the lattice 
command line in the following input file.

Sorry to disturb you, but I need your help.

Best wishes,
Tsuneo Hirano
Emeritus Professor of Chemistry, Ochanomizu University, Japan

----- input file --------------------------------------
***, h2o ef
memory,5,m
basis=vdz
geomtyp=xyz
geometry={x,y;  ! C2v
3
H2O
O,  0.0, 0.0, 0.0
H,  0.0, 0.756, -0.591
H,  0.0,-0.756, -0.591
}
lattice,unit=ang;            !  <------
[ 0.0  0.0  2.0 -1.0  0]    ! A point charge of -1.0 is to be placed 
at z = 2.0 Angstrom.

{rhf;
wf,10,1,0}

---