[benner]

I am trying to construct molecular orbital diagram for Ni(H2Im)2 where Im stands for imidazole-2-ylidene. The point group of the molecule is D2h. I used the fragmentation approach to the problem where my fragments are Ni and the two imidazole-2-ylidene. I solved for the reducible representation of the ligand, Im using D5h as a point group. I also obtained the ligand's orbitals using projection method. The reducible representation using D5h point group is A2" + E1" + E2". My next step is match this ligand's orbitals with the metal's orbitals. However, my problem is they have different symmetries. So I need to find the reducible representation of the ligand in D2h to match with the metal's orbital. I am hoping to do this using rotational subgroups. The common subgroup for the two point groups is C2v. So I need first to find the equivalent reducible representation of the ligand in C2v, then find the equivalent reducible representation for D2h. However my problem is I could not find any table for rotational subgroups involving the two point groups (D2h and D5h) so that I could find the equivalent reducible representation of D5h in D2h.