Hi to all.
For my study, I want to calculate the dipole, quadrupole and octupole moments of my complexes.
As a test case, I tried the H2 molecule. The molecule is oriented along the z axis and the center of mass is located at (0,0,0).
According to literature, due to symmetry reasons the components of the quadrupole moments should be: Θxx = Θyy = -Θzz/2 .
However, when i run turbomole (DFT or MP2) , I get completely different results.
Below, I paste the results from a riMP2/def2-TZVPP optimization.
I also get the same results, if I run a properties calculation with the $moments keyword.
nuc SCF,e -> SCF,tot MP2 -> total
------------------------------------------------------------------------------
quadrupole moment
------------------------------------------------------------------------------
xx 0.000000 -1.550279 -1.550279 0.021371 -1.528908
yy 0.000000 -1.550279 -1.550279 0.021371 -1.528908
zz 0.969885 -2.060752 -1.090867 -0.001570 -1.092437
xy 0.000000 0.000000 0.000000 0.000000 0.000000
xz 0.000000 0.000000 0.000000 0.000000 0.000000
yz 0.000000 0.000000 0.000000 0.000000 0.000000
1/3 trace= -1.383418
anisotropy= 0.436472
------------------------------------------------------------------------------
As you can see, the program gives no Θxx = Θyy = -Θzz/2 relation.
Other qc programs, like Gaussian, Gamess and Molpro give the expected results.
Do you have any suggestions?
Do I have to specify a special keyword in the control file?
Thanks in advance,
Antonio.
