The program will write a 101 x 121 x 121 grid on the H2O_bas.sbf which is now updated.
In the case of the T_d group, the best way to exploit symmetry is to put the vertices of the tetrahedron at the vertices of a cube like in the following example:
C 1 (CENTRE 1) 0.98523954 0.98523954 0.98523954 CHARGE = 6.0
C 2 (CENTRE 2) -0.98523954 -0.98523954 0.98523954 CHARGE = 6.0
C 3 (CENTRE 3) -0.98523954 0.98523954 -0.98523954 CHARGE = 6.0
C 4 (CENTRE 4) 0.98523954 -0.98523954 -0.98523954 CHARGE = 6.0
The input for grid09 corresponds to a qurter of a cube, i.e.:
0.05 0.05 -7.25
7.20 7.20 14.5
Then run top_sym with two C2 rotation, one around the x axis, the other around y:
tetrahedrane_ebas.sbf 2
C2X
0.0 0.0 0.0
C2Y
0.0 0.0 0.0