[ironman2538]

Can anyone tell me as to how to assign the molecular orbital of Iron(II) with imine based ligand complexes. For that matter what is E1g, E1u,T2g,T2u,E2g, E2u etc....What does this names indicates..? where can I get the basic info about this...n how to label the Mil orbitals of Iron (II) complexes...?
Thanks   

[darko]

t= three degenerate orbitals
e=two degenerate orbitals
g=center of simetry
2=orbaitals will change sign turning around axis perpeendicular to main axis

Fe(II)....d⁶ so you have to look about strong and week ligand fields impact to that conformation and then get some further conclusions , in basic you should google for ligand field theory and MO theory to get some basic information and then ask for concrete help

ligands supplaying imine nitrogen donor atoms may give stabile low-spin octahedral complexes or distored octahedral (Jahn-Taller), in octahedral field five d-orbitals will split in t₂g and e_g acording to privious explanatios try to place 6 electrons in so split orbitals (complexess are diamagnetic)

[ironman2538]

Thanks buddy,
                     But thts the real qn...according to simple theory it should ideally be diamagentic....but in reality my complexes are paramagnetic....and there have been incidences that some of them are diagmagnetic too....i read somewhere that these kind of imine complexes are not innocent and do interact with iron orbitals and under go spin cross over...do u know anything about it...? how can tht be confirmed..!!! I m reading on it...but its just little difficult to understand...and grasp it.....so i need help on tht part..!!!!! 

[darko]

in this case is posible that high-spin and low-spin are separated in (or near) room temperature. crossover occurs when the spin-pairing energy and orbital spliting  :delta:_o are simillar. that is possible for Fe(II) complexes with nitrogen ligands. due to the absence of the electrons in e_g antibonding orbitals of the low-spin octahedral complexes, the bonds Fe-N are shorter wich will effect lower potential wels. so to  confir this you could measure magnetic susceptibility, run vibrational spectrocopy ...I will hel you ,but you have to be more specificated (I dont know your level of knowlwdge) so any aditional question will help

[ironman2538]

well I m doing my research in Fe complexes....n its catalytic application... i m little comfortable with organic aspect but analysis of it..like inorganic part is little overwhelming....!!! how can you determine if such complexes show spin cross over ....like any analytical technique like NMR, IR, UV-VIs....we have these instru.. 

[darko]

http://cdsweb.cern.ch/record/692617 , hope it helps

[ironman2538]

Thanks...That helped..!!!!! hope i could fine answer from it..!!!!!